1. (NASDAQ: IRGI) William Blair Growth Stock Conference June 25, 2003

2. 5478706 2 Statements contained in this presentation that are forward-looking are based on current expectations that are subject to a number of uncertainties and risks, and actual results may differ materially. Factors that might cause such a difference include, but are not limited to, risks associated with: the reduction in research and development activities by pharmaceutical and biotechnology clients, changes in government regulations, the effects of interest rate and foreign exchange fluctuations, our ability to attract and retain employees, the loss or delay of contracts due to economic uncertainty or other factors, our ability to efficiently manage backlog, our ability to expand our business through strategic acquisitions, competition within the industry and the potential adverse impact of health care reform. Further information about these risks and uncertainties can be found in the information included in the company’s recent filings with the Securities and Exchange Commission, including the company’s Registration Statement on Form S-1 and Form 10-K filed on February 18, 2003. Safe Harbor Disclaimer

3. 5478706 3 Building the world’s leading and most profitable drug development services company

4. 5478706 4 Strategy for Profitable Growth Operational Overview 2002 Financial Overview First Quarter 2003 Financial Overview

5. 5478706 5 Investment Summary Global market presence Full-service drug development capability Large market opportunity Established leadership position in pre-clinical development Unique position in clinical development Diversified revenue mix and client base Proven management team Track record of growth and profitability

6. 5478706 6 Company History 1964Inveresk performs first pharmacology/toxicology studies (in Edinburgh) 1965CTBR (Pre-clinical Americas) founded (in Montreal) 1988Inveresk Clinical Research founded (in Edinburgh) 1989ClinTrials Research founded (in Nashville) 1996ClinTrials Research and CTBR merge 2001Acquisition of ClinTrials by Inveresk Research 2002NASDAQ listing (“IRGI”)

7. 5478706 7 Global Market Coverage Origin of Clients - 2002 USA 56% Europe 31% Japan 7% RoW 6% Client Type Pharma 56% Biotech 32% Other 12%

8. 5478706 8 Full-service Drug Development Capability Pre-clinical Testing, Toxicology, Drug Metabolism & Pharmacokinetic Studies (DMPK) Final Patent Application File IND Marketing Application Market Approval Discovery Research Development Research Regulatory Review Post-Mktg Review Market segments covered by Inveresk Research Basic Research Genomics Proteomics Virtual chemistry Synthesis Biological testing Pharmacological screening Phase I Phase II Phase III Phase IV Clinical Trials

9. 5478706 9 Large Market Opportunity Source: CMR International, IMS Health Growth in R&D vs. Revenue (Indexed) R&D Growth Revenue Growth Market for Outsourced Drug Development Services ($ in billions) Source: Frost & Sullivan CAGR – 13.7%

10. 5478706 10 Pre-clinical Overview World #3 in toxicology World #1 in speciality toxicology Integrated laboratory sciences Established over 35 years ago 85% repeat business Diverse client base Focus on quality, value-added Clients - USA, Europe and Japan % of 2002 Net Service Revenue 64% Revenues - $142.2 million 1,830 Employees Locations – Edinburgh, Scotland and Montreal, Canada

11. 5478706 11 Clinical Overview % of 2002 Net Service Revenue 36% Revenues - $80.3 million 720 Employees Locations – USA, UK, Germany, France, Spain, Italy, Belgium, Poland, Czech Republic Key global capability Phase I-IV coverage European #4 World class Phase I - 62 bed clinic with “first-into-man” focus ClinTrials integration completed successfully Further opportunity for revenue growth and improved profitability

12. 5478706 12 Highly Diversified Client Base Top client – 5.9% Top 5 clients – 21.1% Top 20 clients – 43.2% Percentage of 2002 Net Service Revenue

13. 5478706 13 Proven Management Team Walter Nimmo President & CEO (15 years) Mike Ankcorn President - CTBR (24 years) Brian Bathgate President - Europe (12 years) Pre-clinical Nick Thornton Corp. Development (2 years) Alastair McEwan President (7 years) Clinical Paul Cowan CFO (1 year)

14. 5478706 14 Track Record of Growth and Profitability Acquisition of ClinTrials – April, 2001 (i) Excludes amortization of goodwill prior to 2002 and exceptional charges related to our IPO in 2002 of $54.6 million. Net Service Revenue ($ in millions) Acquisition of ClinTrials – April, 2001 Income From Operations (i) ($ in millions)

15. 5478706 15 Operational Overview Strategy for Profitable Growth 2002 Financial Overview First Quarter 2003 Financial Overview

16. 5478706 16 Response to Market Characteristics IRGI Response Key Market Drivers Drug Industry Trends: Huge demand for new therapeutics Impact of new technologies - genomics Growth of “biotech” and biotech products Increased “pharma” competition Impact on Research & Development: Increasingly demanding regulation Escalating R&D expenditures Need for improved R&D productivity Industry Response: Increasing and more focussed R&D Greater trend to outsourcing Need for global drug development Strategic: Continue focus in earlier development stages – Pre-clinical, Phase I through early Phase III Differentiate through a higher value-added service offering Maintain global reach Concentrate on areas with the highest barriers to entry – toxicology, lab sciences Maintain diverse, high quality client base Provide solutions, not just science Service Offering: Focus on quality and responsiveness Maintain broad based service offering Address both pharma and biotech Continue emphasis on speciality services Leverage Pre-clinical/Clinical cross selling opportunity

17. 5478706 17 Financials - Key Growth Drivers Maintain revenue growth in Pre-clinical, accelerate in Clinical Controlled capacity expansion in Pre-clinical and Phase I – to sustain/enhance operating margins Progress margin expansion in Clinical - towards target levels of 15% to 20% Continue migration of “old ClinTrials” clinical contracts to higher margin business – to be completed in 2003 Maintain emphasis on cost control and improved business processes across all business areas Target bottom line growth of over 20% per annum

18. 5478706 18 20052004 2003 Stage 1 - Montreal Toxicology and Lab Sciences Stage 1 - Edinburgh Toxicology Stage 2 - Edinburgh Lab Sciences Stage 2 - Montreal Toxicology & Lab Sciences Stage 1 – Clinical Europe Phase I Stage 1 – Clinical Americas Phase I Key Elements for Organic Growth

19. 5478706 19 Operational Overview 2002 Financial Overview Strategy For Profitable Growth First Quarter 2003 Financial Overview

20. 5478706 20 2002 Key Highlights IPO completed in June; 12 million shares sold at $13.00 per share Net revenue up 42% to $222.5 million Pro forma operating income up 104% to $45.6 million Full-year operating margin 20.5% 2002 diluted EPS of $0.88, pro forma Cash flow from operations $51.3 million (i) Stage 1 Montreal pre-clinical expansion completed, on time and within budget, and pre-sold on a multi-year basis Reorganization and integration of former loss-making ClinTrials clinical businesses has progressed beyond expectations (i) Before payment of accumulated shareholder loan interest.

21. 5478706 21 2002 Segment Results – Pro Forma (i) Pro forma, excluding amortization in 2001 and exceptional charges in 2002 relating to the Company’s IPO. +104% +95% +100% Income From Operations (i) ($ in millions) +49% +31% +42% Net Service Revenue ($ in millions) 20012002

22. 5478706 22 Relative Profitability - 2002 Peer Group - Mean

23. 5478706 23 Review of Cash Flows Net cash provided by operations: $51.3 million, before deducting accumulated interest of $21.5 million on pre-IPO shareholder loans Capital expenditure: $25.5 million Cash flow (before accumulated shareholder loan interest paid) as a % of Pro forma net income - 155% Net DSO’s at year end: 30 (45 at December 30, 2001) Cash and equivalents at year end: $19.9 million Gross financial debt at year end: $68.0 million

24. 5478706 24 Operational Overview First Quarter 2003 Financial Overview Strategy For Profitable Growth 2002 Financial Overview

25. 5478706 25 Q1, 2003 Financial Highlights Net service revenue up 8.5% to $57.7 million ($53.2 million in Q1, 2002) Income from operations $8.6 million ($5.2 million in Q1, 2002) Pro forma income from operations $9.2 million ($9.8 million in Q1, 2002) Significant rebound in activity levels at our Montreal-based pre-clinical operations Clinical revenues grew 14.3% year-on-year. Operating margin increased to 10.6% in Q1, 2003, from 4.1% in Q1, 2002 Diluted EPS of $0.20, compared to a loss per share of $0.02 in 2002 Pro forma diluted EPS of $0.22, a 22% increase over Q1, 2002 Cash flow from operations $4.8 million, before capex of $4.3 million New business signings $76.6 million in Q1, 2003 Confirmed backlog - $222 million at March 31, 2003

26. 5478706 26 Q1, 2003 Financial Results by Segment Net Service Revenue ($ millions) Income from Operations ($ millions) +5% +14% +9% -6% +194% -15% 20032002 Total Reported Total Pro Forma +64% ClinicalPre- clinical Clinical Total Reported

27. 5478706 27 Key Factors Influencing Q1, 2003 Results Volatility in short-term business flows in Montreal-based pre-clinical operations – strong rebound experienced in March/April Reduced levels of pass-through costs in European pre-clinical operation deflate revenue, but not profitability Continued recovery in clinical business – in terms of growth and profitability Transaction exchange losses recorded totaling $1.5 million – now hedged Social security costs on employee share option exercises booked in Q1 totaling $0.2 million Negative mark-to-market adjustment on interest rate swaps of $0.2 million Share offering costs of $0.7 million expensed in quarter Positive impact of Canadian and UK tax credits, reduced Canadian corporate tax rates and newly available UK tax deductions for share option expenses

28. 5478706 28 Moving Annual Total of Signed Contracts Moving Annual Total of Signed Contracts – cumulative previous twelve months new signed contracts, net of cancellations

29. 5478706 29 Confirmed Backlog

30. 5478706 30 Outlook and Strategy Continued strength in new business signings across all operations Rebound in Montreal-based pre-clinical operations experienced in March and April European pre-clinical operations experiencing continued strong demand for both toxicology and laboratory sciences services Clinical businesses continuing strong performance of 2002 2003 EPS forecast to total between $1.07 and $1.09, on revenue growth of 11% to 14% Continue to service our clients with quality, high value-added services Pre-clinical expansion on track, Stage 1 Montreal expansion pre-sold – leveraging our world leading capability Diverse revenue and client base, positions IRGI well for the future

31. 5478706 31 Investment Summary Global market presence Full-service drug development capability Large market opportunity Established leadership position in pre-clinical development Unique position in clinical development Diversified revenue mix and client base Proven management team Track record of growth and profitability