This article describes a statistical computing system, the Computer-Assisted Data Analysis (CADA) Monitor, for use in performing interactive statistical data analysis.Especially easy to use because of its conversational nature, CADA includes facilities for data management, evaluation of probability distributions, Bayesian parametric models, Bayesian simultaneous estimation, Bayesian full-rank analysis of variance, and exploratory data analysis.CADA is written in a transportable subset of BASIC, and versions are currently available for a variety of computers.