Therapeutic evaluation of nonsteroidal anti-inflammatory drugs in the treatment of acute musculoskeletal diseases and injuries requires the use of adequate models for clinical trials. The objective of a short-term pain study is to determine whether a new treatment is effective and how it compares with a standard or reference drug for the indication being evaluated. Among the requirements for the pain model study are proper protocols and adequate, homogeneous patient populations. Problems in establishing the model include difficulty in finding adequate numbers of patients, inappropriate sites, patient resistance, and varying conditions of natural recovery. Suggestions are presented for conducting these studies: relying on global pain relief scores, keeping a home diary that is simple and objective, and extending the initial observation period in the office to generate single-dose data in a controlled environment. Sports medicine models are useful in allowing investigators the necessary numbers of patients and providing data that meaningfully address pharmacologic treatment for acute musculoskeletal disorders.