This 'thesis' explores the notion of the Other in Heidegger's philosophy. It tries to analyze Dasein's engagement with its Mitdasein from a variety of angles. As well as discussing Heidegger's distinction between being-inthe- world and being-with and concern and solicitude, it looks at the impact of the body, language, temporality and ethics in relation to these. For Heidegger the Other is no fixed entity, but the process of engaging with the world is the primordial ground out of which 'self' and 'Other' emerge. However, the notion of FOrsorge [solicitude], which is meant to capture Dasein's engagement with the Other is in many ways unsatisfactory. Although it provides us with an authentic relation to the Other, it does not allow for any direct disclosure or engagement with the Other, as it is always mediated through the world. It is argued that a more direct engagement with the Other could easily be inserted into Heidegger's philosophy without any need to question any of Heidegger's key concepts (e.g. time) as Levinas does. Heidegger might not discuss our engagement with the Other at any great length and part of the thesis is thinking through these gaps, yet nevertheless being-with is a primordial part of his fundamental ontology. A thinking of being is a thinking of how being emerges within its relations. Thus when Heidegger argues that fundamental ontology is originary ethics, he pOints out Dasein is always already attuned to not only the world around it but also to the Other.