Context: The role of hand hygiene in preventing health care associated infections (HCAIs) has been clearly established. However, compliance rates remain poor among health care personnel. Aims: a) To investigate the health care workers′ hand hygiene compliance rates in the intensive care unit (ICU), b) to assess reasons for non-compliance and c) to study the efficacy of a multimodal intervention strategy at improving compliance. Settings: A mixed medical-surgical ICU of a tertiary level hospital. Design: A before-after prospective, observational, intervention study. Materials and Methods: All health care personnel who came in contact with patients in the ICU were observed for their hand hygiene compliance before and after a multimodal intervention strategy (education, posters, verbal reminders and easy availability of products). A self-report questionnaire was also circulated to assess perceptions regarding compliance. Statistical analysis was done using c2 test or Fisher exact test (Epi info software). Results: Hand hygiene compliance among medical personnel working in the ICU was 26% and the most common reason cited for non-compliance was lack of time (37%). The overall compliance improved significantly following the intervention to 57.36% (P<0.000). All health care worker groups showed significant improvements: staff nurses (21.48-61.59%, P<0.0000), nursing students (9.86-33.33%, P<0.0000), resident trainees (21.62-60.71%, P<0.0000), visiting consultants (22-57.14%, P=0.0001), physiotherapists (70-75.95%, P=0.413) and paramedical staff (10.71-55.45%, P< 0.0000). Conclusions: Hand hygiene compliance among health care workers in the ICU is poor; however, intervention strategies, such as the one used, can be useful in improving the compliance rates significantly.