High content imaging (HCI) is the quantification of the rich complexity of cellular biology using automated, high performance microscopy and multiparametric data analysis. HCI assays can be target-based, where a specific pathway or target of interest is quantified using one or two features with a known relationship to associated biology. Phenotypic profiling is an alternative approach where morphological changes in cells are quantified by measuring many features. Distinct phenotypic profiles can then be identified and compared between treatment groups. Both target-based HCI assays and phenotypic profiling can be leveraged for early drug discovery, including target validation and high throughput screening workflows. This presentation will give a brief overview of HCI technology and describe the broad range of biological questions relevant to early drug discovery that can be addressed using a variety of HCI techniques.