As a priest, he served as [[dean]] of the Cathedral of St. Sophia in Washington, DC, from 1934 to 1960.
Elected [[titular bishop]] of Harioupolis in 1960, he was [[consecration of a bishop|consecrated to the episcopacy]] on [[November 6]], 1960, at St. Sophia's. He oversaw the archdiocesan districts of Chicago and Charlotte, respectively, until his retirement in 1973.
Bishop Aimilianos died in 1992. In 1998, the Washington City Council named a park across from St. Sophia's Cathedral in the Bishop's honor. The park is maintained by the ''Bishop Laloussis Foundation'' of Bethesda, Maryland.