In order to better prepare the medical, graduate and undergraduate students participating in our international medical mission trip to Nicaragua, we prepared and presented a discussion on Oral Rehydration Therapy (ORT) prior to the international experience. Additionally, a clinical simulation experience was incorporated into our pre-departure training to instruct the students on basic clinical skills, medical interviewing and teamwork. As a tool to measure the students’ prior knowledge on the topic of ORT, we designed a questionnaire, which was distributed and collected prior to the training and simulation experience. Finally, one day after the ORT training and simulation experience, we distributed the same questionnaire and collected the results in order to measure the efficacy of the training and simulation on the students’ perspective of confidence, as well as the students’ retention of the information and skills taught. Our study population consisted of 9 first-year medical students, 1 graduate student, and 16 pre-medical students, all of whom participated in all aspects of the study. In the pre-training survey, only five of the students indicated that they could confidently and effectively explain or administer ORT to someone else. After collecting the results from the post-training survey, all of the students indicated that they could confidently and effectively explain or administer ORT to someone else. We concluded that the ORT training and clinical simulation experience, wherein students could actively apply the knowledge they gained on the administration of ORT to patients, are effective tools to aid in the preparation of medical, graduate and undergraduate students by way of increasing students’ level of confidence in the subject material prior to embarking on international medical mission trips.