In this workshop, we will cover the fundamentals of clinical trial designs: phase I, II and III clinical trial designs, both Bayesian and frequentist approaches, sample size and power calculation. In particular, we will discuss the 3+3 design, continual reassessment method (CRM) and Bayesian model averaging BMA-CRM, for dose finding in phase I clinical trials. For phase II trials, we will discuss two-stage designs, and also randomized trial designs with predictive probabilities and adaptive randomization. In phase III trials, we will cover group sequential methods and frequentist adaptive designs. In addition, we will discuss various adaptive randomization schemes and dose-finding methods for drug-combination trials. As treating patients with a combination of agents is becoming commonplace in cancer clinical trials, the primary focus is to induce biochemical synergism. We will illustrate these statistical methods under various practical scenarios based on recent clinical trials at M. D. Anderson Cancer Center. No prior knowledge in biology or medicine is assumed; we provide the necessary biomedical background when the statistical problems are introduced. Specific topics: Fundamentals of Clinical Trials Frequentist versus Bayesian Statistics Phase I Clinical Trial Design Phase II Clinical Trial Design Phase III Clinical Trial Design (Power and Sample Size) Adaptive Randomization Drug-combination Study