Dispensing quality and chemists' depth of expertise were evaluated in a descriptive cross-sectional survey of 206 independent drugstores. In September 2011 and April 2012, researchers in Dar es Salaam, Tanzania, gathered their data. The proficiency of drug dispensers handling controlled substances was evaluated using a patient simulator (mystery shopper) technique. A seven-day supply of metronidazole pills was purchased from each pharmacy and used to evaluate dispensing competence. Focus groups and one-on-one interviews were used to evaluate the drug dispensers' expertise in the area of distributing prescription-only medications. The most majority (70.4%), however, did not have any formal pharmaceutical training. Skills in dispensing were either very poor (25.7% of those surveyed) or quite high (70.4%). The majority of chemists and other medical professionals surveyed (11.4%) reported having just a moderate or low degree of awareness regarding distributing 'prescription only' medications. These results support the need for the National the Pharmacy Council to institute measures to guarantee that only properly educated chemists are responsible for dispensing prescription drugs. Strengthening the competence of drug distributors also requires an emphasis on on-the-job training and ongoing professional development.