The widening participation (WP) policy agenda directs higher education institutions (HEIs) in England to deliver measures aimed at increasing participation rates among under-represented groups. A central aspect of this is the idea that targeting must be used to reach individuals belonging to these groups. However, the detail of how to go about putting this into practice has largely been left to the interpretation of HEIs and the staff working within them to deliver WP. Drawing upon in-depth interviews with WP practitioners to gain insight into how this policy is being enacted on the ground, this paper will demonstrate how external and situated contexts shape the interpretation of targeting; in particular, the closely interlinked contextual factors of an institution's position in the HE market, makeup of its student body, and nature of its relationship to the regulator. Furthermore, examining how social class, ethnicity and gender feature within targeting approaches, it will show how different contextual factors make certain target groups possible while effectively precluding others.