Critical thinking skills in the healthcare field are imperative when making quick-thinking decisions. This descriptive comparative study investigated to what extent completing a critical thinking course improved college students' critical thinking skills. The study further investigated whether the instructors' critical thinking skills were important to students' learning in the course. Four instructors and the 60 students enrolled in critical thinking classes completed the Critical Thinking Basic Concept Test (OCTBCT) prior to the beginning of the course to determine pre-course critical thinking skills levels. The students completed the test at the end of the course to determine whether their critical thinking skills had improved. The students' gain scores were correlated to the instructors' pre-course test scores to determine whether a relationship existed between the instructors' critical thinking skills on five dimensions of critical thinking and the students' critical thinking gain scores on the five dimensions. Data revealed students' scores improved but not significantly on four of the dimensions of critical thinking and decreased on one dimension. Correlation data revealed a non-significant relationship between instructors' pre-course test scores although students' post-course scores were higher in the classes taught by instructors with higher OCTBCT scores. Implications for practice and recommendations for further research were made. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]