Background: Active involvement of relatives has the potential to improve postoperative patient outcomes by prevention of complications sensitive to basic care and unplanned readmissions. The aim of this study was to assess the feasibility of a program in which relatives participated in postoperative care.; Methods: A pragmatic feasibility trial conducted at the surgical ward of a University hospital in the Netherlands. Patients undergoing esophageal or pancreatic resection with a relative who was willing and able to participate formed the intervention group (n = 20). A control group (n = 20) received usual postoperative care. The program consisted of the following: (1) information; (2) shared goal setting; (3) task-oriented training; (4) participation in basic care, focusing on mobilization, breathing exercises, cognitive activities and oral hygiene; (5) presence of relatives during ward rounds; and (6) rooming-in. Feasibility criteria were adherence to basic care, caregiver burden, and satisfaction of patients, family, and healthcare professionals.; Results: All participants completed the program. Patients in the intervention group mobilized more (estimated difference for walking 170 meters per day, P = .037, and for sitting 109 minutes per day, P < .001), and showed more adherence to breathing exercises (estimated difference per day 1.4, P = .003), oral hygiene (estimated difference 1.52, P = .001), and cognitive activities (estimated difference 2.6, P < .001). Relatives'Care-Related Quality of Life instrument score did not deteriorate over time (P = .64); 96% of relatives would recommend the program and 92% felt better prepared for discharge. Patients in the intervention group were more satisfied with hospital admission. Healthcare professionals valued the program positively.; Conclusion: This program is feasible and is positively appreciated by patients, family, and healthcare professionals. Patients following the program showed more adherence to basic care activities.