In the RFCS project MartBain the 1-step Q&P annealing strategy is investigated and compared with both TBF (Trip Bainitic Ferrite) and conventional 2-step Q&P annealing. Various compositional effects on bainite formation below Ms are studied with the aim to optimize alloy design for achieving high strengths combined with short austempering (partitioning) times below Ms. The holding time at the austempering temperature is of key importance since it controls the amount of bainite formed and thereby also the stability of the remaining austenite. Decomposition of this remaining austenite to hard fresh martensite during the final cool to RT is often detrimental for the properties, in particular for the local formability as measured through HEC (Hole Expansion Coefficient) testing. Plates of eight steel compositions are heat-treated with 300 s holding at a temperature of approximately 30 ºC below Ms which leads to ~ 25 % martensite. The results show that a 0.24C-1.7Mn-1.5Si-0.6Cr alloy has higher bainite kinetics than 0.24C-2.3Mn-1.5Si steel while both compositions deliver UTS ~ 1400 MPa combined with YS ~ 1000 MPa, TE ~ 9% and HEC ~30 %. Modern annealing lines are sometimes equipped with active cooling in the austempering section for adequate control, for example to take away all latent heat accompanying bainite formation in order to achieve an isothermal temperature. In the last part of this study an adapted process is investigated whereby the latent heat of bainite formation is utilized to effectively obtain 2-step Q&P annealing. The temperature is assumed to increase proportionally with the amount of bainite formed. The rate at which the temperature increases depends on the bainite kinetics and will be less than achieved with an inductor as used in the normal 2-step Q&P process.