This thesis explores the theory that International Humanitarian Non-governmental Organisations (IHNGOs) have increasingly become part of the world-ordering security agenda of developed western states since the end of the Cold War. It argues that the adoption of humanitarian aid and development activities by intervening military forces in Afghanistan, criticised by IHNGOs for blurring the boundaries between humanitarian and military actors, is a symptom of, rather than the central reason for, reduced humanitarian space in Afghanistan. This study contends that the central issue is the wider integration of political, military and humanitarian action into the process of state-building as a way to pacify areas of conflict and instability that otherwise present potential security threats to the developed world. This has become even more pronounced with the aims of the Global War on Terror (GWOT) since 2001. The merging of humanitarian aid and development with security in the pursuit of stable states has occurred as an international response to the humanitarian crises and intra-state wars since the end of the Cold War. Military involvement of this kind is typified in Afghanistan by Provincial Reconstruction Teams (PRTs) that combine security and development action. During the 1990s humanitarianism also underwent a metamorphosis as concern about the role aid could have in fuelling conflict and a desire to ameliorate the underlying causes of poverty and conflict led many aid agencies to adopt a new vision of humanitarianism that had political and social goals beyond those of just meeting the immediate needs of populations in crisis. Another feature of humanitarian interventions of the 1990s was the ambitious expectations placed upon IHNGOs and intervening military forces from the international community to manage or resolve these crises without a corresponding level of long-term political, economic and military commitment. These issues are also present in post-2001 Afghanistan where IHNGOs initially supported an international intervention and a new government which has since been faced with a growing insurgency. Consequently, involvement with state-building, governance, rights and development have placed IHNGOs at odds with the insurgents. A case study approach is used to examine five major IHNGOs and how they fit into the context of the international state-building project in post-2001 Afghanistan. The central finding of this study is that the integration of humanitarian aid and development into state-building as a means to enhance international security has seriously compromised the claims to the principles of neutrality, impartiality and independence central to the concept of humanitarian space and consequently the security of the IHNGOs in the ongoing Afghanistan conflict. To overcome these problems this study suggests that IHNGOs should place their humanitarian aid activity under a separate umbrella organisation that operates under the neutral, impartial and independent principles adhered to by the International Committee of the Red Cross (ICRC), the organisation in this study that has managed to maintain some acceptance and dialogue with all parties to conflict.