The influence of an environmental enrichment programme on the searching behaviour of separate groups of male and female bush dogs at Edinburgh Zoo was evaluated. The enrichment programme involved hiding food in specially constructed wood-piles and other appropriate places in the bush dogs' enclosures. Behavioural data were recorded morning and afternoon for 20 consecutive experimental days and were compared to pre- and post-enrichment programme data, representing basal conditions. Data were collected over a 10-day period for both pre and post enrichment phases. Activities were recorded under seven behavioural categories. There was no significant difference between sexes in the proportion of time spent performing searching behaviour so data were pooled. The enrichment programme appeared to cause an increase (P < 0.01) in searching behaviour from initial basal conditions of 2.7 per cent to 6.1 per cent of total recorded data points. There was a subsequent decrease in searching behaviour (P < 0.01) to 2.5 per cent when basal conditions were reinstated. All dogs showed increases in searching behaviour when enrichment and basal data were compared. The effectiveness of the enrichment programme in terms of increasing the proportion of time spent in searching behaviour showed a significant decline (P < 0.005) over time, probably relating to the dogs increasing proficiency at finding food. It is suggested that the enhanced levels of searching behaviour represent an improvement in welfare.