Proactive deprescribing is the process of tapering or stopping a medicine before harm occurs. This study aimed to specify and validate, with an international sample of healthcare professionals, a proactive deprescribing process of steps and constituent activities. We developed a proactive deprescribing process framework of steps which we populated with literature-derived activities required to be undertaken by healthcare professionals. We distributed a survey to healthcare professionals internationally, requesting for each activity the frequency of its occurrence in practice and whether it was important. Extended response questions investigated barriers and enablers to deprescribing. The 263 survey respondents were from 25 countries. A proactive deprescribing process was developed comprising four steps: (1) identify a patient for potential stop of a medicine, (2) evaluate a patient for potential stop of a medicine, (3) stop a medicine(s), and (4) monitor after a medicine has been stopped, and 17 activities. All activities were considered important by ≥70% of respondents. Nine activities required healthcare professionals to undertake in direct partnership with the patient and/or caregiver, of which seven were only sometimes undertaken. Deprescribing interventions should include a focus on addressing the barriers and enablers of healthcare professionals undertaking the activities that require direct partnership with the patient and/or caregiver.