Nursing is a scientifically rigorous discipline which requires updated information on a regular basis to ensure that best possible care is provided to the patients.The aim of the study is to evaluate the Effectiveness of Capacity Building Program regarding the use of Assessment Scales for critically ill patients in terms of Knowledge of Nurses. Pre–Experimental study using One Group Pre–test Post–test design with total enumeration sampling technique was used to enroll 36 Nurses who directly involved in patient care in the Liver Coma ICU, ILBS. A Structured Knowledge Questionnaire was prepared to assess the Knowledge of Nurses regarding the use of Assessment Scales (Glasgow Coma Scale, Pupil Reaction Scale and Modified Ramsay Sedation Scale). The Mean Post–test Knowledge Scores were significantly higher than the Mean Pre–test Knowledge Scores. Study concluded that the Capacity Building Program was effective in enhancing the Knowledge of Nurses regarding the use of Assessment Scales