  Recent progress in generalised geometry and extended field theories suggests
a deep connection between consistent truncations and dualities, which is not
immediately obvious. A prime example is generalised Scherk-Schwarz reductions
in double field theory, which have been shown to be in one-to-one
correspondence with Poisson-Lie T-duality. Here we demonstrate that this
relation is only the tip of the iceberg. Currently, the most general known
classes of T-dualities (excluding mirror symmetry) are based on dressing
cosets. But as we discuss, they can be further extended to the even larger
class of generalised cosets. We prove that the latter give rise to consistent
truncations for which the ansatz can be constructed systematically. Hence, we
pave the way for many new examples of T-dualities and consistent truncations.
The arising structures result in covariant tensors with more than two
derivatives and we argue how they might be key to understand generalised
T-dualities and consistent truncations beyond the leading two derivative level.

High Energy Physics - Theory