This research note is to provide an understanding of Critical Core Skills (CCS) use in Singaporean workforce. Drawing on a sample of 2000 random participants from the workforce, the study developed an instrument based on SSG CCS framework to group the participants into seven occupation groups according to similar CCS use pattern within each group. Practical applications of the instrument developed in this study include: (i) skills needs analysis and evaluation for CCS development interventions, (ii) job-worker matching for career counsellors and employment agencies, and (iii) direction of skills development policy through the identification of areas requiring directed effort.