Adverse environmental conditions, such as extreme temperatures, are detrimental to plant growth and development and thus, affect the productivity of various crops around the world. In recent years, maize (Zea mays L.) production has expanded into short season environments that require early planting into cold and wet soils. Therefore, an important goal for maize breeders is to develop elite germplasm sources for inbred lines that are able to grow under these challenging conditions. The objective of this research is to evaluate direct and correlated responses of two cycles of S₁ and full-sib recurrent selection for cold tolerance, on two improved maize populations. One population was developed and improved at North Dakota State University, NDSCD(M)C₁₀, and the other population was developed and improved at Iowa State University, BS22(R)C₇. The S₁ and full-sib progenies were obtained by selfing 100 random plants and by intercrossing 200 random plants respectively. Ten percent of the families were selected and recombined at the same time in our summer nursery based upon data across northern ND locations achieving one year per cycle of selection based upon progenies. Recurrent selection was based on emergence percentage, seedling vigor, and root lodging resistance.