Ralph Lainson was a distinguished protozoologist and a parasitologist of many abilities. Above all, he was a naturalist, as reflected both by his approach to work and by his two principal hobbies, fishing and collecting butterflies. Besides this, he had a strong artistic streak, expressed by his love of playing the trombone and painting. Many of his published works are exquisitely illustrated with his own watercolour and pen and ink drawings. These talents are present throughout his scientific career. He was a ‘traditional protozoologist’, who wanted to find out how parasites were transmitted and related to each other. Although many of the organisms he discovered were associated with a disease, Ralph openly admitted that his ultimate interest would always be the parasite. His research methods were simple, but he would readily embrace a technology if it solved his problem. He admitted to not being good with equipment. As an example, he mentioned an aptitude test used by the British Army: to put together a dismantled bicycle tyre pump—for him this was an impossible task! This shows his ability to use such tales to get others to do tasks he preferred not to, as they distracted him. His self-control was remarkable; in the 30 years that we worked together, I cannot remember a single instance of him raising his voice to anybody. He was extremely dedicated to whatever he did, be it work, hobbies or play. His stories at the dinner table or around a campfire, when out in the field, were a source of joy that reflected his good nature.