In this talk I discuss the naturalness problem of particle physics, arguing that the standard model (SM) is free of such problem, but this is kind of accidental, thanks to the values of the top and Higgs mass. The real problem arises in extensions of the SM where all couplings are O(1). However, the naturalness problem is brought under control in models with extra particles that have feeble couplings with the SM. We discuss the application of this idea to the Two-Higgs doublet model.