Introduction. The COVID-19 pandemic exposed professionals in geriatric services to overwhelming workload and psychological distress. A study conducted during the pandemic with Italian participants working in geriatric services of Pio Albergo Trivulzio showed that women, professionals aged above 45, physicians, and participants with low levels of resilience were at higher risk for distress. A longitudinal intervention study was thus designed to promote mental health and job satisfaction of professionals working in this institution through the mobilization and development of individual, team, and organizational resources. Three data collection phases were planned: at the beginning of the study (T0), after six (T1) and 12 months (T2). Based on the results obtained at T0, training courses on well-being at work and team building, psycho-educational and organizational interventions will be implemented, monitoring related outcomes at T1 and T2. Method. At T0 198 workers (physicians, nurses, rehabilitation professionals, healthcare assistants, and administrative staff) completed a battery of instruments, including the Mental Health Continuum-Short Form, the Job Satisfaction of Health Professionals, and the Assessment of Interprofessional Team Collaboration Scale II (comprising partnership, cooperation, and coordination subscales). Data were compared across professional roles through ANOVA. Results. As concerns mental health, 55% of the participants reported moderate levels, 31% were flourishing, and 14% languishing. No significant differences across professions emerged for positive mental health levels and job satisfaction. Regarding interprofessional collaboration, ratings of coordination aspects were lowest across healthcare professions. Administrative staff scored significantly lower than all healthcare workers for partnership and coordination, except for coordination values that did not differ from those reported by rehabilitation professionals. Discussion/Conclusion. Results highlighted the need to enhance teamwork skills and foster shared decision-making processes, also involving administrative staff. Interventions scheduled in the next research phases will be aimed at strengthening organizational and teamwork resources and supporting workers’ well-being.