Seed security exists when men and women within the household have sufficient access to quantities of available good quality seed and planting materials of preferred crop varieties at all times in both good and bad cropping seasons. Measuring seed security is important in crisis and non-crisis situations as seed insecurity is not confined to post-disaster settings, although it may be at its most acute at these times. This publication provides practical guidance on the theory, technical knowledge, procedures and good practices necessary to implement a Seed Security Assessment (SSA), which should be a fundamental pre-cursor to seed related interventions.