The study was conducted in the Sindh province of Pakistan to assess the performance of Extension Field Worker (EFWs) performed during FAO-EU-ADB funded National Integrated Pest Management Programme (Nat-IPM) for cotton. The basic principle of Nat-IPM programme was to enable farmers to be self sufficient, using practices that are agro-ecological friendly. This study was carried out in four districts of Sindh province (Hyderabad, Tando Allahyar, Matiari, and Mirpurkhas). The sample size comprised 48 EFWs who participated in Training of Facilitators (ToF) and erecuted FFSs during 2001 and 2004. The results revealed that the EFWs performed effectively to attain the objectives of IPM programme. It appears that EFWs improved farmers' knowledge, skills and behavioral change in attitude towards agro-ecological sound IPM practices through FFS training.