Sentence-final particles in Japanese are a class of particles that are used at the end of a surface form of a sentence, and indicate a speaker's attitude, emotions, feelings or strategy in presenting information to an addressee. The focus of this study has been to examine the male use of sentence-final particles, in particular those associated with the male gender (and hence 'masculinity'). Recent studies in Japanese sentence-final particles have focused on 'feminine' sounding particles. There is a need to examine the subtle nuances and implications of the use of 'masculine' particles and their combinations. This will address a poorly understood area of Japanese conversational techniques among foreign learners. The use of sentence-final particles in informal Japanese dialogue was assessed by collecting examples which occurred in contemporary Japanese novels, comics and television drama scripts. These provided data from a cross-section of the Japanese community in a wide range of contexts. The examples were analysed according to a number of criteria including the social relationship of the speaker and addressee, the emotional state of the speaker, the type of strategy adopted, and any response to the utterance. The particles examined in this study are divided into three categories depending on the type of force involved: 1. Coercive force (including zo, ze, yo and no when used as a command) 2. Emotive force (including i, na, wa) 3. Requestive force (including ka, ne and no used in questions) The particles in each of these categories were then sub-divided further based on the type of strategy adopted, the common speech acts referenced, and the gender of the speaker. The particle clusters are seen to be combinations of these strategies, and reflect the nature of the individual particles. This study establishes that Japanese males tend to use particles associated with coercive force, and more direct strategies, more frequently than females, although the precise choice of particle will vary considerably from individual to individual. The direct approach in Japanese is often associated with coarseness, and so the more direct particles are restricted to particularly intimate conversation amongst friends.