The MOBILE2 Randomized Clinical Trial aimed to assess whether mechanical and oral antibiotics bowel preparation (MOABP) reduces overall complications and surgical site infections (SSIs) compared to mechanical bowel preparation (MBP) plus placebo in patients undergoing elective rectal resection. The trial was conducted at three university hospitals in Finland from March 18, 2020, to October 10, 2022, involving 565 patients. Patients were randomized in a 1:1 ratio to receive either MOABP or MBP plus placebo. The primary outcome was the Comprehensive Complication Index (CCI), and key secondary outcomes included SSI and anastomotic dehiscence within 30 days post-surgery. Key findings indicated that MOABP significantly reduced overall postoperative complications (median CCI, 0 vs 8.66; P < .001), SSIs (odds ratio, 0.45 [95% CI, 0.27-0.77]), and anastomotic dehiscences (odds ratio, 0.39 [95% CI, 0.21-0.72]) compared to MBP plus placebo. Subgroup analyses suggested that the benefits of MOABP were most pronounced in patients undergoing open low rectal resection. The study concluded that MOABP should be considered as a standard treatment for elective rectal resection due to its effectiveness in reducing overall complications, SSIs, and anastomotic dehiscences. Further follow-up is needed to evaluate long-term outcomes, particularly oncological aspects.The MOBILE2 Randomized Clinical Trial aimed to assess whether mechanical and oral antibiotics bowel preparation (MOABP) reduces overall complications and surgical site infections (SSIs) compared to mechanical bowel preparation (MBP) plus placebo in patients undergoing elective rectal resection. The trial was conducted at three university hospitals in Finland from March 18, 2020, to October 10, 2022, involving 565 patients. Patients were randomized in a 1:1 ratio to receive either MOABP or MBP plus placebo. The primary outcome was the Comprehensive Complication Index (CCI), and key secondary outcomes included SSI and anastomotic dehiscence within 30 days post-surgery. Key findings indicated that MOABP significantly reduced overall postoperative complications (median CCI, 0 vs 8.66; P < .001), SSIs (odds ratio, 0.45 [95% CI, 0.27-0.77]), and anastomotic dehiscences (odds ratio, 0.39 [95% CI, 0.21-0.72]) compared to MBP plus placebo. Subgroup analyses suggested that the benefits of MOABP were most pronounced in patients undergoing open low rectal resection. The study concluded that MOABP should be considered as a standard treatment for elective rectal resection due to its effectiveness in reducing overall complications, SSIs, and anastomotic dehiscences. Further follow-up is needed to evaluate long-term outcomes, particularly oncological aspects.