| Summary of Revenues by Geographical Region and Reportable Segment |
The Company attributes revenues to geographical region based upon where the services are performed. The following tables represent revenues by geographical region and reportable segment for the years ended December 31, 2025, 2024 and 2023:
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2025 | | (in millions) | | Technology & Analytics Solutions | | Research & Development Solutions | | Contract Sales & Medical Solutions | | Total | | Revenues: | | | | Americas | | $ | 3,363 | | | $ | 4,105 | | | $ | 277 | | | $ | 7,745 | | | Europe and Africa | | 2,646 | | | 2,273 | | | 266 | | | 5,185 | | | Asia-Pacific | | 617 | | | 2,518 | | | 245 | | | 3,380 | | | Total revenues | | $ | 6,626 | | | $ | 8,896 | | | $ | 788 | | | $ | 16,310 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2024 | | (in millions) | | Technology & Analytics Solutions | | Research & Development Solutions | | Contract Sales & Medical Solutions | | Total | | Revenues: | | | | Americas | | $ | 3,182 | | | $ | 3,894 | | | $ | 280 | | | $ | 7,356 | | | Europe and Africa | | 2,397 | | | 2,304 | | | 219 | | | 4,920 | | | Asia-Pacific | | 581 | | | 2,329 | | | 219 | | | 3,129 | | | Total revenues | | $ | 6,160 | | | $ | 8,527 | | | $ | 718 | | | $ | 15,405 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | December 31, 2023 | | (in millions) | | Technology & Analytics Solutions | | Research & Development Solutions | | Contract Sales & Medical Solutions | | Total | | Revenues: | | | | Americas | | $ | 3,091 | | | $ | 4,157 | | | $ | 304 | | | $ | 7,552 | | | Europe and Africa | | 2,156 | | | 2,103 | | | 200 | | | 4,459 | | | Asia-Pacific | | 615 | | | 2,135 | | | 223 | | | 2,973 | | | Total revenues | | $ | 5,862 | | | $ | 8,395 | | | $ | 727 | | | $ | 14,984 | |
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