Joint INFN/SNS/UniPi Theory Group Seminar. In the framework of the AdS/CFT correspondence, a phenomenological approach can be used to construct gravity dual theories that reproduce many of the features for four-dimensional Yang-Mills theory and QCD. The simplest model for the pure glue sector consist in Einstein gravity plus a single scalar field in five dimensions. Within an appropriate class of scalar field potentials these models reproduce many qualitative features of strongly coupled large-N Yang-Mills theory and one can adjust the parameters so that the accord with lattice results is very good at the quantitative level. I will describe how spectra, thermodynamic quantities and various transport coefficients are computed in the gravity dual language, and I will briefly discuss extensions to include flavor dynamics.