Staffing needs planning, as distinct from workforce planning, is the systematic estimation of the actions personnel managers must take to provide the required workforce in an organization. This handbook focuses on the pivotal aspects of staffing needs planning, including estimation of future vacancies and analysis and projection of employee turnover. The first section of the book briefly introduces staffing needs planning and the policy issues related to it. The second section explains details of manual methods of projecting turnover losses, including the nature of the retention curve and fitting and using the log-probability curve. Section 3 presents computer methods for analyzing turnover, advancement, and hiring needs, including LOGPRO, LPFILE, LPTEST, GS810, and HIREST. The handbook is designed for use by those with limited statistical training as well as by those who are technically proficient. The computer programs are intended to be general in application, complete, compact, simple, and fully documented. Appendices provide detailed documentation on the manual methods and the computer programs, including full computer program listings, operation manuals, and technical analysis. (Author/JM)