Currently, the City of Rotterdam is far from achieving their ambitious 2020 goal of a 40% household waste separation rate. In 2017, their separation rate was only 28,4%. Household waste separation is important to enable the recycling of resources. For high-rise buildings, the challenge is the biggest: high-rise buildings produce an average of 150 kg more residual waste per year compared to low-rise buildings. The City of Rotterdam’s plans to build more high-rise buildings in the coming years makes it urgent to look for a solution. Separation at the source currently is more effective than mechanical post-consumer separation. However, the success of separation at the source depends entirely on the waste separation behaviour of high-rise residents. Therefore the main research question is: How to facilitate for high-rise residents the desired behaviour of waste separation at household level, in high-rise buildings? From human behaviour theory, behaviour can be explained as a combination of one’s motivation, ability, and opportunity. When one’s motivation is low, a low ability needs to be sufficient to trigger action. A change of environment can support a behaviour change. The many influencing factors for waste separation found in literature show the complexity of the behaviour. The factors are supported and complemented by interviews and generative research. Understanding high-rise residents’ mindset towards household waste separation, reveals four different groups of people: the Enthusiasts, the Potentials, the Skeptics and the Conservatives. The Potentials are closest to following the Enthusiasts in practising waste separation. However, they currently lack a (physical and mental) system for doing so. When considering starting this behaviour, the required effort for creating a system outweighs their medium level of motivation. The proposed solution is Schone start. Schone start supports high-rise residents with the creation of a waste separation habit in the first month after moving, by providing the means to set-up a system for waste separation. The mail delivery package contains a Waste guide, Waste map, small waste bin, medium waste bag, large waste box, stickers and suggestions for use. All essential information to start waste separation is actively provided and in accordance with the circular ambitions of the City of Rotterdam. Schone start is evaluated with six recently moved high-rise residents in Rotterdam. Generally Schone start is positively evaluated by the test participants regarding helpfulness with household waste separation. The Waste guide and Waste map were highly appreciated. The waste facilities were partially used, but can be optimised. The ease of disposal of the separated waste stays a critical boundary condition. To implement Schone start, its design should be optimised for appearance and size to maximise the percentage of citizens making use of the product. It is recommended to evaluate the long-term quantitative effect (the household waste separation rate) and qualitative effect (awareness of the household waste separation practice) of Schone start in a large scale pilot over six months. In this way, more insights can be gained regarding the potential impact of Schone start for different target groups and contexts.