One of the most remarkable examples of self-organized structure formation is the development of a complex organism from a single fertilized egg. With the identification of many molecules that participate in this process of morphogenesis, attention has now turned to capturing the physical principles that govern the emergence of biological form. What are the physical laws that govern the dynamics and the formation of structure in living matter? Much of the force generation that drives morphogenesis stems from the actomyosin cortical layer inside cells, which endows the surface of the cell with the ability to generate active forces and stresses that can drive reshaping. We combine theory and experiment and investigate how the actomyosin cell cortex self contracts, reshapes and deforms, and how these physical activities generate left-right asymmetric structures. I will report on projects from the lab that investigate the early development of nematodes and birds, where we have applied concepts from active chiral matter theory to shed light on chiral development and the physical mechanisms that underlie left-right symmetry breaking.