The multi-adversity resistance (MAR) program is an exact science for genetic improvement that is developing cottons with increasingly higher levels of resistance to many adversities (diseases, insects and environmental stresses) in production. Sequential increases in levels of broad hast resistance are producing strains that stay healthier throughout the growing season. The sequential improvement for maintaining plant health is paralleled by improvement in earliness and total realizable lint yield. Host resistance, earliness and yield data are presented which document the achievement of further improvement in MAR as represented by the MAR-4 strains Tamcot CAB-CS and CDP37HH-1-83.