In this chapter I will be drawing from my experience as Force Commander (FC) of the defunct United Nations Mission in Sudan (UNMIS) and of the United Nations Mission in the Republic of South Sudan (UNMISS) and focus on the inter-communal crisis that took place in Jonglei State, South Sudan, at the turn of the year (December 2011/January 2012).1 I begin by outlining the background to the UNMISS and then cover the current challenges of the military force in implementing the mission mandate. This chapter focuses on the nature of UNMISS operations and covers in some detail the operations in Jonglei in order to analyze and outline some of the challenges that I and my staff faced in carrying out the UN mandate. In addressing this topic I equate land forces with UN military forces as UN military forces have generally been land forces. The aim of this chapter is to discuss the challenges for land forces in military operations using UNMISS as a case study. This chapter begins with a section on the background of UNMISS in order to discuss the roles of UNMISS Force, their deployment and configuration. It then highlights the security challenges to UNMISS operations including InterTribal violence and security challenges posed by the armed opposition forces.