Achieving sustainability-related targets in construction projects is increasingly becoming a key performance driver. Yet sustainability is a complex concept in projects and there are many diverse stakeholders. Some stakeholders are generally recognized as important, i.e., the client and main contractor, yet there are others not always perceived as such and whose absence from the decision-making processes may result in a failure to address sustainability issues. Hence there is a need for a systematic approach to engage with stakeholders with high salience in relation to sustainability. This paper reports the results of an exploratory study involving interviews with construction project practitioners that are involved in sustainability in some way. Data were collected from the practitioners in terms of the processes for engaging with stakeholders to deliver sustainability. The data suggests six steps to a stakeholder engagement process: (i) identification; (ii) relating stakeholders to different sustainability-related targets; (iii) prioritization; (iv) managing; (v) measuring performance; and (vi) putting targets into action. The results suggest that understanding the different sustainability agendas of stakeholders and measuring their performance using key performance indicators are important stages to be emphasized in any stakeholder engagement process to achieve sustainability-related goals.