For decades the IS community has been struggling with the delivery of low quality systems. Software process improvement (SPI) programs are accepted as one of the remedies to overcome this problem, with process maturity being a key element. A major contributor of process maturity is the capability maturity model integration (CMMI). However, most studies regarding process maturity and the determinants of IS quality have been conducted in large firms in developed countries. But it is imperative for software development firms both large and small to understand what is needed to deploy high quality systems. This study seeks to assess the determinants of process maturity in firms in the English-speaking Caribbean (ESC), using the established practices in the CMMI as a baseline for discussion and analysis. Applying PLS as the analytical tool, it was found that project monitoring and control, and verification and validation are major determinants of process maturity in the ESC. These findings can assist practitioners in their pursuit to produce higher quality software products, as well as provide a platform for further refinement of the research model by IS researchers.