A new, solution-processable, low-bandgap, diketopyrrolopyrrole-benzothiadiazole-based, donor-acceptor polymer semiconductor (PDPP-TBT) is reported. This polymer exhibits ambipolar charge transport when used as a single component active semiconductor in OTFTs with balanced hole and electron mobilities of 0.35 cm(2) V(-1)s(-1) and 0.40 cm(2) V(-1)s(-1), respectively. This polymer has the potential for ambipolar transistor-based complementary circuits in printed electronics.