A laboratory colony of an Ethiopian sand fly, Phlebotomus longipes, was maintained over a period of 3 years in a London laboratory through 9 generations of a 1st colony and 7 generations of a 2nd colony. Breeding was carried out successfully on a plaster-of-Paris base in a newly designed breeding vessel, the “Tower-vial,” modified from the KM-vial, which was also employed in earlier stages of colonization. The larval diet initially consisted of autoclaved rabbit feces for the earlier generations, but in later generations liver, or yeast, formed the main constituent of the larval diet. First-stage larvae were attracted to these diets which resulted also in rapid growth and a high percentage of larvae pupating to yield adults. At 25°C, females oviposited from 11 to 95 eggs (mean 52) 7–9 days after a full blood meal; eggs hatched 7–8 days later. The mean life cycle from egg to adult emergence was shortest (about 45 days) on a larval diet of liver. Feeding of adults on a sugar solution, and of females on blood from man and other animals is described. Females fed most readily on the human arm 2 to 3 days after emergence. Sugar-fed males and females lived as long as 35 days, and blood-fed females lived for 5–6 days and occasionally longer (about 10 days) at 80% rh and 25°C in cages in an insectary. At least 3 partial blood meals could be taken by a female in 5 days. These findings are consistent with P. longipes being competent as a vector of cutaneous leishmaniasis in Ethiopia. Copulation was preceded by courtship (epigamic behavior). A single male mated with more than 1 female and inseminated 3 out of 5 females over a 24-hr period.