"Cellular models are needed to study human development and disease in vitro, and to screen drugs for toxicity and efficacy. Current approaches are limited in the engineering of functional tissue models with requisite cell densities and heterogeneity to appropriately model cell and tissue behaviors. This talk will describe how spheroid bioprinting in suspension baths can be used to engineer high-cell density microtissues of prescribed spatial organization. Example applications of this technology will include bioprinting induced pluripotent stem cell-derived cardiac microtissue models with spatially controlled cardiomyocyte and fibroblast cell ratios to replicate the structural and functional features of scarred cardiac tissue that arise following myocardial infarction, including reduced contractility and irregular electrical activity. It will also describesd how these models can be used for screening miRNA therapeutics targeting cardiomyocyte proliferation for cardiac regeneration. Recent advances in bioprinting high-cell density tissues with controlled cellular organisation will also be described. These methods are useful for a range of biomedical applications, including the development of precision tissue models with advanced physiological relevance."