Stevenson, DanielVozzo, RaymondDrown, Matthew2025-06-132025-06-132025https://hdl.handle.net/2440/145169This thesis constructs a new model for the homotopy theory of spaces. In particular, we equip the category of simplicial groupoids with a new model structure which we demonstrate is Quillen equivalent to the Kan-Quillen model structure on the category of simplicial sets. We also take the first steps in developing an associated classifying theory for principal groupoid bundles.enThesis