In this talk I will present recent work that includes models that fall in the category of Bayesian nonparametrics; a flexible framework for modelling complex data of unknown latent dimensionality. I will start my talk with a brief overview of Bayesian and nonparametric modelling. I will continue with presenting Bayesian nonparametric models for relational data, e.g. social networks and gene expression analysis. The talk aims to provide an overview of what is Bayesian and nonparametric modelling and how it can be used in real applications.