The retarding and the accelerating activities of some modified thiocarbamyl sulfenamides—namely,N-cyclopentamethylene thiocarbamyl-N′-(cyclohexyl, thiocyclohexyl) sulfenamide (CPCTS),N-cyclopenta-methylenethiocarbamyl-N′-(cyclohexyl,N-cyclopentamethylene thio) sulfenamide (CPCCS), andN-cyclopentamethylenethiocarbamyl-N′-(cyclohexyl,N-oxydiethylene thio) sulfenamide (CPCOS)—have been studied in dibenzothiazyl disulfide (MBTS)-accelerated vulcanization of natural rubber (NR). It is found that CPCTS, CPCOS, and CPCCS delay the onset of cure and generate active accelerators during vulcanization. In addition to this, the accelerator systems are quite capable of producing age-resistant vulcanizates. The results indicate that thiocarbamyl sulfenamides modified chemically at the >NH functionality retain their accelerating property. Thus CPCTS, CPCOS, and CPCCS play the dual role of an accelerator and a retarder in the vulcanization of NR accelerated by MBTS.