AbstractAs in many large organizations with graded staffs, promotions of R.N. officers above the junior ranks depend on vacancies created by retirement and other losses and by promotions from the rank above. Career prospects are a function of age distributions and wastage rates and of fluctuations in the size of the Navy. There are three entry streams with different conditions and prospects. Career planning consists in regulating the sizes of the different streams, and of transfers between them, so as to produce maximum stability in promotion prospects at desired levels, consistent with maintaining the correct strengths and retaining flexibility. Close statistical control is necessary, involving long-term career models and shorter-term forecasts. The actuarial techniques used can also be applied to assess civilian staff career prospects, whether or not career planning methods are in operation.