Background: Improved complementary feeding is cited as a critical factor for reducing stunting. Consumption of meats has been advocated, but its efficacy in low-resource settings has not been tested. Objective: The objective was to test the hypothesis that daily intake of 30 to 45 g meat from 6 to 18 mo of age would result in greater linear growth velocity and improved micronutrient status in comparison with an equicaloric multimicronutrient-fortified cereal. Design: This was a cluster randomized efficacy trial conducted in the Democratic Republic of Congo, Zambia, Guatemala, and Pakistan. Individual daily portions of study foods and education messages to enhance complementary feeding were delivered to participants. Blood tests were obtained at trial completion. Results: A total of 532 (86.1%) and 530 (85.8%) participants from the meat and cereal arms, respectively, completed the study. Linear growth velocity did not differ between treatment groups: 1.00 (95% CI: 0.99, 1.02) and 1.02 (95% CI: 1.00, 1.04) cm/mo for the meat and cereal groups, respectively (P = 0.39). From baseline to 18 mo, stunting [length-for-age z score (LAZ) <-2.0] rates increased from ̃33% to nearly 50%. Years of maternal education and maternal height were positively associated with linear growth velocity (P = 0.0006 and 0.003, respectively); LAZ at 6 mo was negatively associated (P < 0.0001). Anemia rates did not differ by group; iron deficiency was significantly lower in the cereal group. Conclusion: The high rate of stunting at baseline and the lack of effect of either the meat or multiple micronutrient-fortified cereal intervention to reverse its progression argue for multifaceted interventions beginning in the pre- and early postnatal periods. This trial was registered at clinicaltrials.gov as NCT01084109. © 2012 American Society for Nutrition.