The AdS/CFT correspondence has long been used as a tool for understanding non-perturbative phenomena in QCD-like theories. In its original form, the correspondence proposes a duality type IIB string theory on AdS₅xS⁵ and N = 4 supersymmetric Yang-Mills gauge theory. In this thesis, we investigate extensions to the original correspondence that allow one to construct dual supergravity theories to other gauge theories that are more similar to QCD. We study renormalisation group flow as a smooth deformation of the supergravity background.  We then investigate dual models including quarks and chiral symmetry breaking in certain D3-D7-brane systems and propose a simple test to determine which supergravity backgrounds will exhibit chiral symmetry breaking behaviour. We go on to describe how improved action ideas from lattice QCD can be incorporated into the correspondence to improve the ultra-violet region of the dual theories. Finally we calculate meson and glueball spectra in the AdS/QCD approach, finding results in good agreement with experimental and lattice data.