It is of paramount importance to improve application techniques when controlling locust outbreaks in developing countries. Most available documents and publications on locust control deal mainly with insecticides, rather than application techniques and the required control equipment. The present guide book is designed to make up for this oversight. Basic principles for conducting spraying operations, descriptions of spraying equipment - especially for ultra low volume spraying - and specific locust control techniques are described in detail. The document explains how to get the most from treatments while minimizing the adverse effects to the man and environment. This book is aimed at decision-makers and all those involved in locust control who wish to improve their knowledge of application techniques. Contents: Introduction. 1 - Spraying principles: Target and active ingredient; Droplet dispersai and deposit; Modes of spraying; Droplet transport; Assessment of spraying. 2 - Spraying equipment: Portable equipment; Vehicle-mounted sprayers; Aerial equipment. 3 - Acridid control treatments: Intervention tactics; Practice of treatments; Inspection and optimization of control operations. Conclusion. References