The ability of clinical trials to measure cutaneous T cell lymphoma (CTCL) has allowed physicians and regulatory reviewers to assess the response of the disease to experimental therapies. The goals of therapy are remission, palliation, and improvement of survival. Given the chronic nature of the disease, surrogate markers for survival are used in clinical trials. The surrogate markers and the validity of the surrogate markers used to date will be compared and contrasted. Tumor burden measurements by way of skin scoring are the parameters most commonly used to assess the response to therapy. Skin scoring systems have used global mapping, severity recording, or target lesions to assess any change in response to an intervention. The advantages and limitations of global and focal scoring are presented, along with examples of skin scoring systems for the five most recently completed trials for CTCL. Measures of palliation are performed via questionnaires. General and CTCL‐specific questionnaires have been developed that assess both discrete and global manifestations of the disease. Those measures of palliation that have been shown to correlate with skin scoring are presented for inclusion into future studies. In addition, study terms such as relapse and freedom from relapse can now be defined with reproducible molecular techniques. Every stage of CTCL warrants further clinical trials, and guidelines for future investigations are proposed.