This study investigated the perceptions of short-term assignments of medical services among participating health care professionals dispatched from Taiwan to underdeveloped areas. Structured questionnaires were mailed to four groups of professionals (physicians, pharmacists, nurses, and public health personnel) who had participated in any of 88 medical missions dispatched to 24 allied nations. A total of 278 returns were valid for analysis. Among them, 222 respondents reported that they had participated in just one overseas medical mission (79.9%). The majority of physicians, pharmacists, and nurses listed humanitarianism as their foremost incentive for participation. In contrast, public health personnel most frequently reported that they had been assigned to the mission abroad. Pharmacists, nurses, and public health personnel most commonly stated that their top goal was health care; but physicians said that aiding Taiwan’s diplomatic relations was their main motive. While all groups generally recognized language proficiency and cultural awareness as important for conducting successful short-term medical aid missions (STMMs), many members of groups did not rate their own capabilities in those area as sufficient, especially pharmacists (p < .001). Orientation for participants and training for local health workers were seen as relatively insufficient. In conclusion, there are considerable differences in the thoughts about STMMs across four key groups of heath personnel. The findings can help inform efforts to integrate evidence into the deployment of STMMs.