SURVSIM: Stata Module to Simulate Complex Survival Data. survsim simulates survival times from parametric distributions and user-defined hazard functions. Standard distributions available include the exponential, Gompertz and Weibull. Alternatively, a user defined [log] [cumulative] hazard function can be specified, in Mata code using colon operators, with survival times generated using a combination of Gaussian quadrature and root finding techniques. Finally, survival times can be generated under cause-specific hazard models for competing risks, using standard parametric distributions. Baseline covariates and complex time-dependent effects can also be specified.Keywords: survival analysis, survival time, Weibull distribution