A study has been performed under contract from ESA/ESTEC identifying the development needs in Europe in the field of new green propellant utilization. Criteria for green propellants are defined and discussed. Promising propellants are identified together with their rating w.r.t. those criteria, in particular establishing a measure of the toxicity. Two application fields are considered: (1) high thrust, which aims at first and second stages of launchers; and (2) low thrust, which considers orbital propulsion of upper stages and future space vehicles like space planes. Propulsion concepts are shown with their technological solutions. The development needs w.r.t. the existing technology status in Europe are identified and prioritised, and corresponding laboratory experiments are given.