Background In the past decade, there has been increasing guideline development for short-term medical missions (STMMs) traveling from high-income to low- and middle-income countries for the purpose of supporting health care services. The ethics of STMMs is criticized in the literature and there is frequently a lack of host country collaboration. This typically results in guidelines which are developed through the lens of the sending (high-income) countries’ staff and organizations. The aim of this paper is to evaluate an existing best practice guideline document from the perspective of host country participants with knowledge of STMMs from Honduras, Malawi, and the Philippines. Methods The guideline used for the evaluation consisted of nine best practice elements that were discerned based on literature and the experience of those working within the field. Semi-structured interviews were conducted in a cross-sectional study with participants (n = 118) from the host countries. Thematic analysis was conducted by two researchers and the results were assessed by working group members to confirm interpretations of the data. Results Overall, participants expressed a strong interest in having more structured guidance surrounding STMM practices. There was a positive response to and general acceptance of the proposed STMM guidelines, although participants found the 24-page document onerous to use; a companion checklist was developed. The key themes that emerged from the interviews included collaboration and coordination, care for hard-to-reach communities, capacity building, critical products and essential medical supplies, and opportunity and feasibility. Conclusions Host input suggests that the guidelines provide structured regulation and coordination of the medical mission process and have the potential to improve the way STMMs are carried out. The guidelines have also proven to be a useful tool for the actual implementation of STMMs and can be a tool to strengthen links and trust between mission teams and local health staff. However, local contexts vary considerably, and guidelines must be adapted for local use. It is recommended that STMM teams work in conjunction with host partners to ensure they meet local needs, increase capacity development of local health workers, and provide continuity of care for patients into the local system.