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At present, producing dense complex-shaped ceramic parts require time-consuming and labour intensive processes, that are unsuitable for large-scale mass production. This results in prohibitively expensive part costs, in turn limiting the range of practical applications for complex-shaped dense ceramic materials. With process modifications, the freeze-casting process has potential as a suitable near-net shaping process for this application. In freeze-casting, a well-dispersed suspension of particles, such as a dispersion of ceramic powder in a carrier solvent, is frozen in a mould to produce a solid part. The frozen solvent can then be removed by sublimation in a freeze dryer, to produce a ceramic green body. Sintering this part enables us to produce a dense ceramic part retaining the shape of the mould. Current research in the field of freeze-casting elsewhere is primarily focused on tailoring the freezing process, to create solvent-crystals of various morphologies, for use as pore-forming templates in the production of highly porous components. In this thesis, freeze-casting was performed with highly loaded non-aqueous alumina ceramic suspensions, primarily with submicron alumina in cyclohexane carrier solvent, with the end-goal of producing dense ceramic components. Previous progress in this research area has been hindered by the samples exhibiting severe internal cracking. In this thesis the mechanisms and key factors responsible were identified for crack formation within samples, and applied this new understanding to explore selected avenues for mitigating the formation of cracks through changes to the process and to the suspension composition. In this work, the role of each of the primary freeze-casting process steps (freezing, freeze-drying and pressureless sintering) were systematically explored relating to both microstructure development and crack formation. A range of techniques were used to examine internal sample microstructures, including micro computed