Getting Strategy Right
Professor Michael E. Porter
Harvard Business School
Leaders in London
London, UK
November 29, 2007
This presentation draws on ideas from Professor Porter’s books and articles, in particular, Competitive Strategy (The Free Press, 1980); Competitive
Advantage (The Free Press, 1985); “What is Strategy?” (Harvard Business Review, Nov/Dec 1996); “Strategy and the Internet” (Harvard Business
Review, March 2001); and a forthcoming book. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or
by any means—electronic, mechanical, photocopying, recording, or otherwise—without the permission of Michael E. Porter. Additional information may
be found at the website of the Institute for Strategy and Competitiveness, www.isc.hbs.edu. Version: November 26, 2007, 6pm
200071129 – London – Final.ppt
1
Copyright 2007 © Professor Michael E. Porter
How Managers Think About Competition
COMPETING TO BE THE
BEST
COMPETING TO BE UNIQUE
• The worst error in strategy is to compete with rivals on the same
dimensions
200071129 – London – Final.ppt
2
Copyright 2007 © Professor Michael E. Porter
Flawed Concepts of Strategy
• Strategy as action
–
–
–
–
“Our strategy is to merge…”
“… internationalize…”
“… consolidate the industry…”
“… outsource…”
• Strategy as aspiration
– “Our strategy is to be #1 or #2…”
– “Our strategy is to grow…”
– “Our strategy is to be the world leader…”
• Strategy as vision
– “Our strategy is to meet our customers’ needs…”
– “… offer superior products…”
– “…to advance technology for mankind…”
200071129 – London – Final.ppt
3
Copyright 2007 © Professor Michael E. Porter
Setting the Right Goals
• The fundamental goal of a company is superior long-term return on
investment
• Growth is good only if superiority in ROIC is achieved and sustained
– ROIC threshold
• Profitability must be measured realistically, capturing the actual profits
on the full investment
• Profitability metrics besides ROIC (e.g., return on sales; ebitda
margin; pro-forma earnings; and cash flow margin) are risky for
strategy
• Prevalent accounting adjustments to reported profitability
(e.g., writeoffs, restructuring charges) can obscure true
economic performance and lead to bad competitive choices
• Goodwill must be treated as part of investment
• Setting unrealistic profitability or growth targets can undermine
strategy
200071129 – London – Final.ppt
4
Copyright 2007 © Professor Michael E. Porter
Economic Performance versus Shareholder Value
Economic
Performance
Shareholder Value
• Sustained ROIC
• Stock Price
• Sustainable Revenue Growth
• EPS
• EPS Growth
• Shareholder value is the result of creating real economic value
• Pleasing today’s shareholders is not the goal
200071129 – London – Final.ppt
5
Copyright 2007 © Professor Michael E. Porter
Economic Foundations of Competition
• The fundamental unit of strategic analysis is the industry
− Defining the relevant industry is important to strategy
• Company economic performance results from two distinct causes
Industry
Structure
Relative Position
Within the
Industry
- Overall Rules of Competition
- Sources of Competitive Advantage
• Strategy must encompass both
200071129 – London – Final.ppt
6
Copyright 2007 © Professor Michael E. Porter
Disaggregating Economic Performance:
Industry vs. Position
35%
31.4%
30.8%
30%
Return on
Invested
Capital
1985-2002
25%
25.4%
20%
15%
10%
9.6%
5%
0%
Reebok International
Paccar
Industry Average
Note: ‘Invested capital less excess cash’ is the average of the beginning period and the ending period values. Excess cash is calculated by subtracting cash in
excess of 10% of annual revenue.
Source: Compustat (2007), author’s analysis
200071129 – London – Final.ppt
7
Copyright 2007 © Professor Michael E. Porter
Profitability of Selected U.S. Industries
1992 - 2006
Security Brokers and Dealers
Soft Drinks
Prepackaged Software
Pharmaceuticals
Perfume,Cosmetic,Toilet Prep
Advertising Agencies
Distilled Spirits
Semiconductors
Surgical and Medical Instruments
Mens and Boys Clothing
Tires
Household Appliances
Malt Beverages
Child Day Care Services
Household Furniture
Drug Stores
Grocery Stores
Iron and Steel Foundries
Cookies and Crackers
Mobile Homes
Wine and Brandy
Bakery Products
Engines and Turbines
Book Publishing
Laboratory Equipment
Oil and Gas Machinery
Soft Drink Bottling
Knitting Mills
Hotels
Catalog, Mail-Order Houses
Airlines
ROIC = Earnings before
interest and taxes divided by
invested capital less excess
cash
Average industry ROIC
in the US:14.9%
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
Return on invested capital, 1992 – 2006 average
Note: ‘Invested capital less excess cash’ is the average of the beginning period and the ending period values. Excess cash is calculated by subtracting
cash in excess of 10% of annual revenue.
Source: Compustat (2007), author’s analysis
200071129 – London – Final.ppt
8
Copyright 2007 © Professor Michael E. Porter
Determinants of Industry Profitability
Threat of Substitute
Products or Services
Bargaining Power
of Suppliers
Rivalry Among
Existing
Competitors
Bargaining Power
of Buyers
Threat of New
Entrants
200071129 – London – Final.ppt
9
Copyright 2007 © Professor Michael E. Porter
Shifting the Basis of Competition
Dimensions of Competition
Price
Same Dimension(s)
(zero sum)
Non Price
Worst
Homogeneity of
Competition
Different Dimensions
200071129 – London – Final.ppt
10
Copyright 2007 © Professor Michael E. Porter
Is There A Sixth Force?
• Industry growth rate
• Technology and innovation
• Government
• Complementary products and services
• Effect on profitability depends on how each attribute affects the five
forces
200071129 – London – Final.ppt
11
Copyright 2007 © Professor Michael E. Porter
Strategic Implications of Industry Structure
1. Positioning to Mute the Five Forces
Heavy Truck Industry
Threat of Substitute
Products or
Services
• Railroads
• Water transportation
Bargaining Power
of Suppliers
• Large suppliers of
engines and drive
train components
Rivalry Among
Existing
Competitors
• Heavy price
competition on
standardized models
Bargaining Power
of Buyers
• Large fleets
• Leasing companies
• Owner operators
Threat of New
Entrants
• Many truck producers
are assemblers
200071129 – London – Final.ppt
12
Copyright 2007 © Professor Michael E. Porter
Paccar Competitive Positioning
• Focus on owner-operators
• Design trucks with special features and amenities
• Customization and build-to-order
• Achieve low truck operating costs
• Offer extensive roadside assistance to truckers
200071129 – London – Final.ppt
13
Copyright 2007 © Professor Michael E. Porter
Strategic Implications of Industry Structure
2. Shaping Industry Structure
Foodservice Distribution Industry
Threat of Substitute
Products or Services
• Go direct
• Use retail / warehouse channels
Bargaining Power of
Suppliers
• Food processors
• Food cooperatives
• Farmers
Rivalry Among
Existing
Competitors
• Distributors
–Purchasing
–Warehousing
–Delivery
Threat of New
Entrants
Bargaining Power
of Buyers
•
•
•
•
•
Restaurants
Schools
Hospitals
Cafeterias
Other food service
establishments
• Low barriers to entry
200071129 – London – Final.ppt
14
Copyright 2007 © Professor Michael E. Porter
Reshaping Industry Structure
Foodservice Distribution
• Offering value-added services
• Offering private-label products
• Moving to national procurement contracts
• Increasing the use of sophisticated information technology
200071129 – London – Final.ppt
15
Copyright 2007 © Professor Michael E. Porter
Determinants of Relative Performance
Differentiation
(Higher Price)
Competitive
Advantage
Lower Cost
200071129 – London – Final.ppt
16
Copyright 2007 © Professor Michael E. Porter
Economics of Strategic Positioning
Southwest Airlines
Revenue and Cost per Available Seat Mile, Average of 1998 - 2000
12
10
Operating Profit per
Available Seat Mile
Pricing
Differential:
1.72
Cost
Advantage:
2.44
8
Cents
per ASM
6
Operating Cost per
Available Seat Mile
4
2
0
Southwest
Note:
Source:
Airline Industry Average
ASM (Available Seat Miles) defined as total seats available multiplied by miles flown
Airline annual reports and author’s calculations
200071129 – London – Final.ppt
17
Copyright 2007 © Professor Michael E. Porter
Foundations of Economic Performance
The Value Chain
Firm Infrastructure
(e.g. Financing, Planning, Investor Relations)
Human Resource Management
Support
Activities
(e.g. Recruiting, Training, Compensation System)
Technology Development
(e.g. Product Design, Testing, Process Design, Material Research, Market Research)
M
(e.g. Components, Machinery, Advertising, Services)
Inbound
Logistics
Operations
(e.g. Incoming
Material
Storage, Data
Collection,
Service,
Customer
Access)
(e.g. Assembly,
Component
Fabrication,
Branch
Operations)
Value
a
Procurement
r
g
Outbound
Logistics
Marketing
& Sales
After-Sales
Service
(e.g. Order
Processing,
Warehousing,
Report
Preparation)
(e.g. Sales
Force,
Promotion,
Advertising,
Proposal
Writing, Web
site)
(e.g. Installation,
Customer
Support,
Complaint
Resolution,
Repair)
i
n
What
buyers are
willing to
pay
Primary Activities
• Competing in a business involves performing a set of discrete
activities, in which competitive advantage resides
200071129 – London – Final.ppt
18
Copyright 2007 © Professor Michael E. Porter
Achieving Superior Performance
Operational Effectiveness is Not Strategy
Operational
Effectiveness
Strategic
Positioning
• Assimilating, attaining, and
extending best practices
•
Run the same race faster
200071129 – London – Final.ppt
Creating a unique and
sustainable competitive
position
Choose to run a different race
19
Copyright 2007 © Professor Michael E. Porter
Five Tests of a Good Strategy
• A unique value proposition
compared to other organizations
• A different, tailored value chain
• Clear tradeoffs, and choosing what
not to do
• Activities that fit together and
reinforce each other
• Strategic continuity with continual
improvement in realizing the
strategy
200071129 – London – Final.ppt
20
Copyright 2007 © Professor Michael E. Porter
Strategic Positioning
Enterprise Rent-A-Car
Distinctive
Activities
Value Proposition
• Numerous, small, inexpensive offices in each
• Home-city replacement cars for drivers
whose cars are being repaired or who need
an extra vehicle, at low rates (30% below
airport rates)
metropolitan area, including on-premises offices at
major accounts
• Open during daylight hours
• Deliver cars to customers’ homes or rental sites, or
deliver customers to cars
• Acquire new and older cars, favoring soon-to-be
discontinued older models
•
Keep cars six months longer than other major
rental companies
• In-house reservations
• Grassroots marketing with limited television
• Cultivate strong relationships with auto
dealerships, body shops, and insurance adjusters
• Hire extroverted college graduates to encourage
community interaction and customer service
• Employ a highly sophisticated computer network to
track the fleet
200071129 – London – Final.ppt
21
Copyright 2007 © Professor Michael E. Porter
Defining the Value Proposition
What
Customers?
Which
Needs?
• What end users?
• What channels?
• Which products?
• Which features?
• Which services?
What Relative
Price?
• A novel value proposition can also grow the pie/expand the industry
200071129 – London – Final.ppt
22
Copyright 2007 © Professor Michael E. Porter
Strategic Positioning
IKEA, Sweden
Distinctive
Activities
Value Proposition
• Modular, ready-to-assemble, easy to package
• Young, first time, or price-sensitive buyers who
want stylish, space efficient and scalable
furniture and accessories at very low price
points.
•
•
•
•
•
•
•
•
•
•
200071129 – London – Final.ppt
23
designs
In-house design of all products
Wide range of styles in huge warehouse stores
with large on-site inventories
Self-selection
Extensive customer information in the form of
catalogs, explanatory ticketing, do-it-yourself
videos, and assembly instructions
Use Ikea designer names on products to inform
coordinated purchases
Child care provided in the store
On-site, low-cost, restaurants
Long hours of operation
Suburban locations with large parking lots
Principally self-delivery by customers
Copyright 2007 © Professor Michael E. Porter
Strategic Positioning
Whole Foods Markets
Distinctive
Activities
Value Proposition
• Well-lit, inviting supermarket store formats with
• Natural, fresh, organic, and prepared foods and
health items with excellent service at premium
prices
•
•
• Educated, middle class, and affluent customers
passionate about food as a part of a healthy
lifestyle
•
•
•
•
•
•
•
200071129 – London – Final.ppt
24
appealing displays and extensive prepared
foods sections
Produce section as “theater”
Café-style seating areas with wireless internet
for meetings and meals
Each store carries local produce and has the
authority to contract with the local farmers
Information and education provided to
shoppers along with products
High touch in-store customer service via
knowledgeable, non-unionized, highly
motivated personnel
Egalitarian compensation structure
Own seafood procurement and processing
facilities to control quality (and price) from the
boat to the counter
Donates 5% of profits to non-profits
Each store has “green projects,” directed by
employees to improve environmental
performance
Copyright 2007 © Professor Michael E. Porter
Making Strategic Tradeoffs
• Tradeoffs occur when strategic positions are incompatible
– The need for a choice
Sources of Tradeoffs
– Incompatible product / service features or attributes
– Differences in the best configuration of activities in the value chain to deliver
the chosen value proposition
– Inconsistencies in image or reputation across positions
– Limits on internal coordination, measurement, motivation, and control
• Tradeoffs make a strategy sustainable against imitation by established
rivals
• An essential part of strategy is choosing what not to do
200071129 – London – Final.ppt
25
Copyright 2007 © Professor Michael E. Porter
Strategic Tradeoffs
Neutrogena Soap (1990)
• Forgo cleaning, skin softening, and deodorizing
features
• Choose higher costs through the configuration of:
– packaging
– manufacturing
– detailing
– medical advertising
– skin research
• Give up the ability to reach customers via:
– promotions
– television
– some distribution channels
200071129 – London – Final.ppt
26
Copyright 2007 © Professor Michael E. Porter
Strategic Tradeoffs
IKEA, Sweden
Typical Furniture Retailer
IKEA
Product
Product
• Low-priced, modular, ready-to-assemble
designs
• No custom options
• Higher priced, fully assembled products
• Customization of fabrics, colors, finishes,
and sizes
• Design driven by image, materials, varieties
• Furniture design driven by cost,
manufacturing simplicity, and style
Value Chain
Value Chain
• Centralized, in-house design of all products
• Source some or all lines from outside
suppliers
• Medium sized showrooms with limited
portion of available models on display
• Limited inventories / order with lead time
• Extensive sales assistance
• All styles on display in huge warehouse stores
• Large on-site inventories
• Limited sales help, but extensive customer
information
• Long hours of operation
200071129 – London – Final.ppt
• Traditional retail hours
27
Copyright 2007 © Professor Michael E. Porter
Recent Thinking on the Sources of Competitive Advantage
• “Key” Success Factors
• “Core” Competencies
• “Critical” Resources
• Competitive advantage is seen as concentrated in a few parts of the
value chain
200071129 – London – Final.ppt
28
Copyright 2007 © Professor Michael E. Porter
Mutually Reinforcing Activities
Zara Apparel
Word-ofmouth
marketing
and repeat
buying
Cuttingedge fashion
at moderate
price and
quality
Customers
chic but
costconscious
Wide
range of
styles
Global
team of
trendspotters
Majority
of
productio
n in
Europe
Very
frequent
product
changes
Little media
advertising
Advanced
productio
n
machiner
y
Extensive
use of
store
sales
data
Prime store
locations in
high traffic
areas
JIT delivery
Tight
coordination
with 20
wholly-owned
factories
Very
flexible
productio
n system
• Fit is leveraging what is different to be more different
Source: Draws on research by Jorge Lopez Ramon (IESE) at the Institute for Strategy and Competitiveness, HBS
29
200071129 – London – Final.ppt
Copyright 2007 © Professor Michael E. Porter
Strategic Continuity
• Continuity of strategy is fundamental to sustainable competitive advantage
–
–
–
–
e.g., allows the organization to understand the strategy
building truly unique skills and assets related to the strategy
establishing a clear identity with customers, channels, and other outside entities
strengthening the fit across the value chain
• Reinvention and frequent shifts in direction are costly and confuse the
customer, the industry, and the organization
• Maintain continuity in the value proposition
• Successful companies continuously improve in how they realize their value
proposition
– Strategic continuity and continuous change should occur simultaneously. They are not
inconsistent
• Continuity of strategy allows learning and change to be faster and more effective
200071129 – London – Final.ppt
30
Copyright 2007 © Professor Michael E. Porter
Barriers to Strategy
Flawed Concepts
• Misunderstanding of strategy itself
• Poor industry definition
Industry Pressures
• Industry conventional wisdom leads all companies to follow
common practices
• Labor agreements limit ways of configuring activities
• Regulation constrains price, product, service or process alternatives
• Customers ask for incompatible features or request new products or
services that do not fit the strategy
200071129 – London – Final.ppt
31
Copyright 2007 © Professor Michael E. Porter
Overcoming Barriers to Strategy
Internal Practices
• Inappropriate goals and performance metrics bias strategy choices
– Short time horizon
• Rapid turnover of leadership undermines strategic direction to
achieve short-term performance benefits
• A desire for consensus blurs strategic tradeoffs
• Inappropriate cost allocation leads to too many products, services,
or customers
• Outsourcing makes activities homogenous and less distinctive
200071129 – London – Final.ppt
32
Copyright 2007 © Professor Michael E. Porter
Internal Barriers to Strategy
Neutrogena Soap (2005)
•
Prior to the 1990’s Neutrogena was the
number one brand recommended by
dermatologists
•
Neutrogena had a relatively narrow target
market but deep penetration and high
customer loyalty
•
Beginning in the early- to mid-1990’s, new
growth-oriented management shifted
Neutrogena from a dermatologist-focused
marketing concept to mass market television
advertisements and celebrity endorsements
•
Neutrogena lost market share while
Gallderma’s Cetaphil captured the loyalty of
dermatologists, and prospered
Source: Draws on research conducted at the Institute for Strategy and Competitiveness and interviews conducted with a former Neutrogena executive.
200071129 – London – Final.ppt
33
Copyright 2007 © Professor Michael E. Porter
Overcoming Barriers to Strategy
Capital Market Biases
• Strong pressure for short-term “surprises” in earnings or revenue
• Strong pressure to grow faster than the industry
• Industry-wide analyst metrics are misaligned with true value and
drive strategic convergence
• Strong pressures to emulate currently “successful” peers
• A strong bias for “doing deals” (M&A)
• Over-weighting of equity-based management compensation
amplifies such unhealthy pressures
200071129 – London – Final.ppt
34
Copyright 2007 © Professor Michael E. Porter
Integrating Strategy and Corporate Social Responsibility
• There is a long-term synergy between economic and social objectives
• Company competitiveness and social conditions can both improve
• Business cannot solve all of society’s problems, nor bear the cost of
doing so
• Business must approach its social agenda strategically
• Where is a company able to have the greatest social impact?
200071129 – London – Final.ppt
35
Copyright 2007 © Professor Michael E. Porter
Strategic Positioning
Whole Foods Markets
Distinctive
Activities
Value Proposition
•
• Natural, fresh, organic, and prepared foods and
health items with excellent service at premium
prices
•
•
• Educated, middle class, and affluent customers
passionate about food as a part of a healthy
lifestyle
•
•
•
•
•
•
•
Well-lit, inviting supermarket store formats with
appealing displays and extensive prepared foods
sections
Produce section as “theater”
Café-style seating areas with wireless internet for
meetings and meals
Each store carries local produce and has the authority
to contract with the local farmers
Information and education provided to shoppers along
with products
High touch in-store customer service via
knowledgeable, non-unionized, highly motivated
personnel
Egalitarian compensation structure
Own seafood procurement and processing facilities to
control quality (and price) from the boat to the counter
Donates 5% of profits to non-profits
Each store has “green projects,” directed by
employees to improve environmental performance
• Excellent strategies often include a social dimension of the value proposition
200071129 – London – Final.ppt
36
Copyright 2007 © Professor Michael E. Porter
Strategic CSR
ChoicePoint
• ChoicePoint’s core business is providing personal identification, screening, and
credit verification
– e.g., access to ChoicePoint databases, employment background screening, credit
verification, DNA identification and authentication, drug testing, etc.
• The company’s CSR program focuses on providing services and advice to social
organizations:
– e.g., Background checks of volunteers working with children such as Boys & Girls Club
volunteers
– Identity verification for Katrina victims
– Assisting NGOs to find missing children and prevent identity theft
• ChoicePoint leverages its skills, data, technological knowledge, and staff to
maximize social impact
• Its CSR approach is aligned with ChoicePoint’s founding principle: creating a safer
and more secure society through responsible use of information
• CSR activities improve the company’s capabilities around identity issues
– Working with social organizations helps develop new methodologies and capabilities
200071129 – London – Final.ppt
37
Copyright 2007 © Professor Michael E. Porter
Strategic CSR
Nestlé in India
• Nestlé’s entered the poor Moga region of India in 1962
• Local milk supply was hampered by small parcels of land, poor soil, periodic
droughts, animal disease, and lack of a commercial market
• Nestlé established local milk purchasing organizations in each town
• Nestlé invested in improving competitive context
– Collection infrastructure such as refrigerated dairies was accompanied by
veterinarians, nutritionists, agronomists, and quality assurance experts to assist
small farmers
– Medicines and nutritional supplements were provided to improve animal health
– Monthly training sessions were held for local farmers
– Wells to secure water supply for animals were dug with financing and technical
assistance from Nestlé
• Nestlé has built a productive milk cluster in Moga, buying milk from more than
75,000 farmers through 650 local dairies
• Moga has dramatically improved social conditions
• Nestlé has developed a long-term competitive advantage in the milk cluster
200071129 – London – Final.ppt
38
Copyright 2007 © Professor Michael E. Porter
Strategy
What is Not a Strategy?
What Is a Strategy?
• A unique value proposition
versus competitors
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
• A different, tailored value chain
• Clear tradeoffs, and choosing what
not to do
• Activities that fit together and
reinforce each other
• Continuity of strategy with
continual improvement in realizing
the strategy
200071129 – London – Final.ppt
39
Best practice improvement
Execution
Aspirations
A vision
Learning
Agility
Flexibility
Innovation
The Internet (or any technology)
Downsizing
Restructuring
Mergers / Consolidation
Alliances / Partnering
Outsourcing
Internationalizing
Copyright 2007 © Professor Michael E. Porter
Communicating a Strategy
• Strategy involves everyone in an organization, not just top management
• The benefits of strategy are greatest when it is communicated widely in the
organization
• Communicating strategy requires a simple and vivid way of describing the
essence of the company’s unique position
– Symbols of the strategy are invaluable tools
– Repetition
• The basic strategy and value proposition must also be communicated to
customers, channels, suppliers, and financial markets
– What about confidentiality?
• Leaders should not assume that subordinates understand the strategy, or that
they agree with it
– Help each organizational unit translate the strategy into implications for its own
mandate
• Individuals who do not ultimately accept the strategy cannot have an ongoing
role in the company
200071129 – London – Final.ppt
40
Copyright 2007 © Professor Michael E. Porter
The Role of Leaders in Strategy
• Lead the process of choosing the company’s unique position
– The CEO is the chief strategist
– The choice of strategy cannot be entirely democratic
• Clearly distinguish operational effectiveness improvement and strategy
• Communicate the strategy relentlessly to all constituencies
– Harness the moral purpose of strategy
• Maintain discipline around the strategy, in the face of many distractions.
• Decide which industry changes, technologies, and customer needs to
respond to, and how the response can be tailored to the company’s strategy
• Measure progress against the strategy using tailored metrics that capture
the implications of the strategy for serving customers and performing
particular activities
• Sell the strategy and how to evaluate progress to the financial markets
• Commitment to strategy is tested every day
200071129 – London – Final.ppt
41
Copyright 2007 © Professor Michael E. Porter
The Moral Purpose of Business
•
The most important thing a corporation can do for society is to contribute to a
prosperous economy
•
Only business can create wealth; other institutions in society are principally involved in
redistributing wealth or investing it to meet human needs
•
Corporations are not responsible for all the world’s problems, nor do they have the
resources to solve them all
– Business has no need to be defensive about its role in society
•
Business has the tools, capabilities, and resources to make a far greater positive
impact on social issues than most other institutions
•
Business is more transparent and more accountable than most foundations and
NGOs
•
Each company can and should identify the particular set of societal problems that it is
best equipped to help resolve, and from which it can gain the greatest competitive benefit
•
Addressing social issues through shared value strategies will lead to self-sustaining
solutions
•
Using these principles, businesses can have a greater impact on social good than any
other institution or philanthropic organization
200071129 – London – Final.ppt
42
Copyright 2007 © Professor Michael E. Porter