Clone IRCA 11 1 was developed in Côte d'Ivoire in 1975 to contribute in increasing the rubber production. Nine years of study were conducted on a large scale to identrfy the optimal tapping system for its exploitation before being released to the producers. The experimental design was that of a Randomised Complete Bloc (RCB). Among the six tapping systems tested (% S d/2 6d/7; % S d/3 6d/7. ET 2.5%. Pa 1 (1). 4/y; % S d/4 6d/7. ET 2.5%. Pa 1 (1). 44; % S d/4 6d/7. ET2.5%. Pa 1 (1). 8/y; % S d/5 6d/7. ET 2.5%. Pa 1 (1). 8/y and % S d/6 6d/7. ET2.5%. Pa 1 (1). 10/y) tapping twice per week with 4 annual stimulations (% S d/3 6d/7. ET2.5%. Pa 1 (1). 4/y) turned out to be the optimal exploitation system for IRCA 11 1. Nevertheless, with a Iimited number of tappers, weekly tapping with 10 annual stimulations (% S d/6 6d/7. ET 2.5 %. Pa 1 (1). 10/y) was the most appropriate. The production of rubber per tree andper tapping (g/t//t) was in logarithmic relation with the intensiw of tapping. The rate of tapping panel dvness (TPD) was related to the intensiw of tapping by a quadratic polynomial function. The study also demonstrated that IRCA 111 had a high yield, a fast growth rate and an active metabolism as compared to the standard clone PB 235.