The present report studies how the distribution of unexploded ordinance (UXO) can be estimated, which is one aspect of the assessment of the remaining risk from UXO on former military firing ranges and training areas after risk reducing measures, such as clearance of the land, have been performed. The report proposes some relatively simple and accessible computational methods to estimate the UXO distribution. These take information and data collected during the clearance of the land as input. The objective of the report is to present an approach for estimating the number of remaining UXO within a subarea of a former military firing range and training area. The method is not able to conclude the exact number of remaining UXO, but rather aims at giving an approximation that can be used as a basis for further risk analysis calculations. Methods for assessing uncertainties are also presented in the report. The proposed method is based on a number of assumptions. In order to use the method these assumptions must be deemed reasonable and accepted for every studied subarea. Assessments of acceptable assumptions must be carried out for every studied case.