In many organisms, the Wingless (Wg)/Wnt signalling pathway regulates developmental processes through Armadillo (Arm)/β-catenin, which activates target gene transcription through the TCF transcription factor family. Now, Tetsu Akiyama and colleagues have identified a new interaction partner for Arm in Drosophila, called Sunspot (Ssp), which acts independently of dTCF (see p. 1755). Using mutant fly lines, the researchers report that Ssp is required for the proliferation of imaginal disc cells, salivary glands and the central nervous system in fly larvae. Ssp controls the transcription of genes involved in proliferation, they report, but although this requires Arm, it is independent of dTCF. By using overexpression studies, the authors also show that Wg negatively regulates Ssp signalling by controlling its subcellular location: Wg expression directs Ssp to the nuclear envelope, away from its targets, in a process that also requires Arm. Given that Wnt signalling is highly conserved, the researchers suggest that Ssp regulation by Wg and Arm might be a general signalling mechanism.