We present recent theoretical and empirical results concerning the accuracy of the Cepheid distance scale based on optical and near-infrared (NIR), reddening free, Period-Wesenheit relations. We also mention the use of Classical Cepheids as tracers of intermediate-mass stars and their use to constrain the heavy element (iron, alpha, CNO elements) abundance gradients across the Galactic disc. Finally, we mention a few recent findings concerning the Cepheid intrinsic properties. In particular, we will focus our attention on new dynamical mass estimates of Cepheids in double-lined eclipsing binaries (1-3% precision) and the mass loss rate of a few Galactic Cepheids based on mid-infrared (Spitzer) and on radio (VLA) measurements.