Abstract Avocado pear, like other fruits, are susceptible to different kinds of damage at and after harvest. Such damage is a major cause of quality loss in avocados. In order to reduce these losses, it is necessary to know the strength properties of the fruit. Such properties help in devising proper equipment for harvesting, storing, transporting, processing and general handling of avocados. Some strength properties of ‘Collison’ avocados were investigated in this paper. It was found that the fruit exhibits superior strength properties at harvest, and the properties generally changed very little within the first 7 days after harvest, after which they reduced rapidly. At harvest, fruits can be packed in wooden boxes up to about 35 layers without damage, while 15 days after harvest they can be packed only about two layers in the boxes. The degree of elasticity at harvest was 87% while 15 days after harvesting it was 40%. At harvest, 25% of the fruits were damaged at a drop height of 500 mm, while 15 days after harvest more than 90% were damaged at the same drop height. Drop heights above 250 mm often resulted in cracking and crushing damage at more than 7 days after harvest. At 15 days post-harvest, fruit were cut twice as fast as freshly harvested ones. At harvest a load of 36 N caused a penetration of 5 mm, while 15 days after harvest 7·5 N caused the same amount of penetration. A load of 10 N caused a penetration of 1 mm at harvest compared to 5·3 mm 15 days after harvest.