The need for personalised and smart products drives the development of structural electronics with mass-customisation capability. A number of challenges need to be overcome in order to address the potential of complete free form manufacturing of electronic devices. One key challenge is the integration of conductive structures and components into 3D printed devices by combining different materials and printing techniques that have nearly incompatible printing conditions. In this paper, several methods to integrate electronic circuits and components into a 3D printed structure are discussed. The functional performance of the resulting structures is described. Structural parts were manufactured with a stereolithography-based 3D printing technique, which was interrupted to pick and place electronic components, followed by either direct writing or squeegee filling of conductive material. A thermal curing step was applied to enhance the bonding and improve the electrical performance. Optical micrography, 4-point resistance measurement and cross-sectional analysis were performed to evaluate functionality.