This chapter highlights the fact that morale is a force that comes from within, and which makes a soldier carry out his duty, but can be influenced by external factors such as regimental loyalty, efficient administration, good leadership and patriotism. It considers a number of methodological issues that are of relevance in developing the study of British Expeditionary Force units. The differences between discipline in Irish and other British regiments are considered, and comparisons between civil and military law are made. Irish soldiers can much more meaningfully be compared with their counterparts in the Scottish highland regiments than with French colonial or Austro-Hungarian troops. Finally, the chapter discusses an issue surrounding discipline and morale that can be meaningfully considered in a thematic form, namely the attempts made to maintain high morale in the Irish regiments during the Great War.