The chronology of the development of the Apollo spacecraft and the lunar mission provides specific documented information covering a wide range of happenings both directly and indirectly related to the program. This wealth of material should be of value to historians and others interested in the events of the great adventure. A discussion of the Apollo Spacecraft Program must include reference to the Mercury and Gemini Programs, not because they are manned space programs but because of the interrelationship between the programs in time, in people, and in organizations, and the differences and similarities in the requirements of the programs. The Mercury Program had a very specific objective, namely to place a man in orbit and return him to earth. The Gemini Program was somewhat different. It was operating in the same earth orbital environment as Mercury but had as its goal a number of objectives which were intended to explore and develop our capabilities to work in this environment. In doing this, the Gemini Program had more resources than Mercury, in terms of increased payload weight in orbit. Apollo is more like Mercury. It has a well-defined objective that involves moving into a new environment-deep space-and resources that offer little if any payload capability beyond that required to achieve the objective. Perhaps the Apollo Applications Program will be to Apollo what Gemini has been to Mercury, establishing an operational capability in an environment which has been first explored in a prior program.