Halide perovskites are compelling candidates for the next generation of clean-energy-harvesting photovoltaic technologies owing to an unprecedented increase in power conversion efficiency and their low cost, facile fabrication and outstanding semiconductor properties. The potential of perovskite materials has been identified by understanding the fundamental science of perovskites such as crystallisation dynamics and charge carrier dynamics and finding various novel perovskite combinations from the periodic table. Current evidence suggests that the synthetic approach applied for the deposition of halide perovskite layers is a key factor dictating device efficiency and stability. In this review, we aim to investigate the large variety of synthetic procedures followed for the deposition of perovskite polycrystalline films and single crystal layers. We will summarize the current understanding and ability to influence material properties by using these synthetic methods and explore the link between synthetic approaches and material properties relevant to photovoltaic and other applications.|Halide perovskites are compelling candidates for the next generation of photovoltaic technologies owing to an unprecedented increase in power conversion efficiency and their low cost, facile fabrication and outstanding semiconductor properties.