A key component of nursing practice is the nurse's ability to process information and to make decisions. One goal of most educational programs for nurses is to enhance students' cognitive abilities and clinical decision-making skills. This study investigated the differences in critical thinking ability and decision-making skills among 121 associate degree, diploma, baccalaureate, and master's-prepared nurses. Results indicated that nurses with master's and baccalaureate degrees had the highest scores in critical thinking ability. Subjects' decision-making skills were measured related to: 1) frequency in making decisions, 2) difficulty in making decisions, and 3) factors which influence decision making. No significant differences were found among the four groups related to the three dimensions of decision-making skills. Experience and knowledge were the most influential factors in decision making. Study findings have implications for investigating differences among nursing students related to cognitive abilities.