The Republic of Ireland, like all other countries, has strict laws governing the crimes of rape and sexual assault. Victims of such assaults are treated in sexual assault treatment units where evidential material is gathered and forwarded to the forensic science laboratory (FSL). This paper represents the first published study from the Republic of Ireland of the time, day and month most frequently encountered in sexual assault cases presented to the FSL. In addition, the study examines the location and nature of the assault, together with such factors as the age of the victim, relationship to the suspect and degree to which the victim has a clear recollection of the events. The study covers information from 890 cases submitted to the FSL in the time period January 2004 to December 2005. The most common age category of victim was 16-30, the most likely time of occurrence was Saturday night/Sunday morning during the summer months of June, July or August. The assailant will most likely be known to the victim even if only recently met. Loss of memory mainly associated with the consumption of alcohol was a significant factor in many of the cases. The figures were compared to international studies with no significant differences between our findings and other studies. We also compared our results to a similar study in 1995-1996 and found little difference except for the number of the victims who were non-Irish nationals: 3% in the 1995-1996 study but by 2004-2005 that figure had risen to 11%.