Global demand for food and farm commodities continues to grow, while land and other natural resources are becoming increasingly scarce. Sustainable intensification is often seen as a new paradigm for increasing agricultural productivity in a socially and environmentally responsible way. Sustainable intensification requires a broad portfolio of technologies, including improved seeds, fertilizers, and various natural resource management (NRM) practices. However, possible synergies between different types of technologies are not yet sufficiently understood. Here, we address this knowledge gap. Using representative data from small farms in Kenya and a propensity score matching approach, we analyze income effects of various technologies and technology combinations. When adopted alone, some innovations produce positive effects, while others do not. Effects of certain technology combinations are larger. The largest income gains occur when improved seeds are adopted together with organic manure and zero tillage practices. This points at important synergies between input-intensive and NRM technologies. Yet, the number of farmers that have adopted such promising technology combinations is relatively small, implying that synergies are not yet fully exploited. More impact studies that explicitly account for possible synergies can add to the knowledge that is needed for designing and promoting technology combinations suitable for particular contexts.