The presented work focuses on the development of novel photoreactive materials for applications in organic electronics. Photopatternable dielectrics are realized by utilizing crosslinking reactions of polynorbornene derivatives with bisazide compounds, as well as by side reactions of the photo-Fries rearrangement. Furthermore, a versatile approach that provides an easy patterning method for cellulose thin films by means of photolithography, is presented. The main concept of this approach is to exploit the acid-induced desilylation reaction of trimethylsilyl cellulose (TMSC) by the use of photoacid generators (PAGs). This method provides the possibility to realize either positive- or negative type structures, depending on the development conditions, with resolutions down to the sub-micrometre range. This biopolymer-based material can therefore be considered as a dual-tone photoresist. The potential application of these dielectric materials in organic electronics is demonstrated by assembling organic thin film transistors (OTFTs) with photopatterned gate dielectrics, exhibiting good performance compared to established materials and processes. These photopatternable dielectric materials enable the realization of electrical interconnects, as required for the fabrication of demanding organic electronic circuits. For the realization of photopatternable electrodes, which are compatible with processes in organic electronics, the photo-induced crosslinking of stabilized gold nanoparticles with a bisazide compound is further explored. Photolithographic patterning of this material leads to nanoparticle patterns with resolutions in the single-digit micrometre range, allowing the fabrication of electrically conductive gold structures by a subsequent sintering step at temperatures below 250 °C. The suitability of these photopatternable electrodes is shown by assembling OTFTs, using such photopatterned gold nanoparticle films as source/drain electrodes.