The mater, al, as presented, dc-es not mwessar,ly reflect any poslt!o" of the IACC m SPE, I% Ofllcers, or members Papers presen!ed at IAOCJSPE meet[ngs are subject to pubhcabon renew by Ed(tor!al Committees of the IACC and SPE Permnss$on to copy ,s restricted to an abstract of not more than 302 wrds Illustrabons may not be cop,ed The abstract should Contain conspicuous acknowledgment ot where and by whom the paper was pres.mted WrKe L!brar,an SPE. PO %x 833-93e Rwhard son TX 75083-3836 USA fax 01-214.952-9435 AbstractThe introduction of roller cone bits incorporating a unique gauge cutting mechanism, in combination with other gauge and hydraulic modifications, dramatically increased drilling cftlcicncy and lowered the costs of t~vo major dci'clopmcnt projects offshore Sarawak, Malaysia, The aforementioned technical modifications and other continuous impro~cmcnt practices, which resulted from close interaction between operator, contractor and bit company, smt' drilling costs reduced neady US$378,000 on the Baram and Baronia devclopmcn! programs, This paper describes the evolution of operator-driwn tool dcvcloprncnt and operational practices that led to incrcascd footage and penetration rate pcr bit in the intcrbcddcd shale, sandstone and limestone intervals intrinsic of the directional NCIISdrilled offshore Sarawak, The authors !vill rcvicnv the tl~o fields (Baram and Baronia). detailing the tool and operational modifications that significantly improicd the economics of the dc~cloprnent drilling campaign