Quenching and Partitioning is enjoying significant attention from steel producing and using communities. A substantial number of studies have employed low carbon transformation induced plasticity steel chemistries and more recent studies have considered richer alloys. Systematic studies detailing effects of varying levels of alloying additions are limited and the present study explores manganese additions ranging from 1.5 over 3 to 5 wt pct to a 0.3C-Mn-1.6Si alloy. Attractive tensile properties with ultimate tensile strength levels exceeding 1500 MPa combined with 20 pct total elongation were obtained in addition to significant retained austenite fractions up to 25 pct at the greatest manganese level employed. The results are compared with previously studied alloys and perspectives on microstructural evolution and properties development will be given. Of particular note is the enhancement of tensile elongation with manganese alloying in addition to improved strength levels. This trend is different from carbon effects where strength level increases are predominantly observed without significant changes to tensile ductility.