Explicitly correlated Gaussian basis is used for solving few-body problems in many fields. The basis functions are easily adaptable and flexible enough to describe complex few-body dynamics. We obtain a unified description of different types of structure and a fair account of correlated motion of interacting particles as well as the tail of the wave function. I present some examples that show the power of the correlated Gaussians: The bound and resonant states of 4He, the electric dipole response functions of 4He and 6He, and alpha-clustering in 16O in the framework of a 12C core plus four nucleon model. It is a challenge for future to extend the application of the correlated Gaussians to a study on a competition between single-particle motion and clustering around a non-inert core. Such a study will be important to evaluate the rate of the radiative capture reactions 12C(alpha, gamma)16O at low energy and to account for the low-lying spectrum of 212Po that shows the large alpha-decay width and the enhanced electric dipole transitions.