Collection of DNA samples from subjects participating in clinical trials is vital to understanding variability in drug response. The purpose of this study was to assess pharmacogenetic sample-collection practices in the industry and to gather information on issues affecting collection. A survey questionnaire was developed and distributed to 20 pharmaceutical companies; 15 provided responses. Assessments included rate of DNA sample collection, reasons for low collection rates, reasons for rejection by health authorities (HAs) and institutional review boards/ethics committees (IRBs/ECs), and country-specific hurdles to sample collection. The results indicated that, although DNA samples are frequently collected, sample-acquisition rates remain lower than expected. Overall, the companies' experience has been that restrictions on sample usage are not consistently applied by regulatory bodies. This may reflect changing opinions/interpretations of HAs/IRBs/ECs. Collection of DNA samples in industry trials is still a challenge. Harmonization of sample-collection practices may facilitate the process.