The high failure rate of development interventions is well known. An approach to sustainable interventions is defined, based on a systems perspective that focuses on the ability of a system to integrate an intervention. The design of an intervention requires an understanding of the current state of the system from the perspective of being able to realise the intended benefit. This is called the readiness of the system, and is constituted by the level of maturity of the essential elements and the nature of the interrelationships that are required to realise and sustain the benefits. Interventions can be designed to match the current readiness of the system and to define the system changes toward the desired end state. These principles were developed during the implementation of an ICT for Rural Education (ICT4RED) project in the Eastern Cape province of South Africa. The practical implications for project design, execution and handover to the education system are illustrated.