A study of the structure and properties of MnAs synthesized by mechanical alloying and powder blending techniques has been carried out. Mechanical alloying resulted in the formation of MnAs during milling. Following heat treatment samples prepared using both techniques exhibited a magnetostructural transformation from the paramagnetic B31 to the ferromagnetic B8(1) phase with decreasing temperature or increasing magnetic field. The transformation temperatures and fields were found to depend on milling procedure and heat treatment conditions. Powder blended and heat treated samples exhibited excellent stability during transformation cycling.