The goal of a Phase III or late-stage development program is to generate an extensive, clinical dataset sufficient to achieve authorization/approval from global health authorities to market the drug, ensure access to the drug from pricing and reimbursement groups, and facilitate uptake of the medication by physicians and patients. Drug developers must balance the increased likelihood of clinical success with the possibility that the populations used to demonstrate efficacy may be specifically indicated in labeling granted by health authorities, thereby limiting market access. In most therapeutic areas, clinical trial endpoints are quantitative and objective. Placebo-controlled trials offer the best opportunity to demonstrate maximal efficacy with the fewest number of patients. Dose-response trials should be conducted in Phase II. There is at least one emerging safety consideration that receives significant attention in CNS clinical trials: the prospective assessment of the occurrence of treatment-emergent suicidality.