Mary Guiney (nee Leahy, 2 March 1901 - 23 August 2004) was an Irish businesswoman and centenarian, best known as the long serving chairperson of Clerys & Co. Early life and education Mary Leahy, known as May in her youth, was born 2 March 1901 at the family farm at Creeves, near Shanagolden, County Limerick. Her parents were John and Hannah Leahy (née Cuddihy) and it is believed she had an older brother and sister, a younger sister and two younger brothers. Her family sent her to the Dominican College in Eccles Street in Dublin. After she left school, she gained employment in Guineys & Co. on Talbot Street, owned by Denis Guiney. Career Leahy married widower Denis Guiney on 19 October 1938, in the St Mary's Pro-Cathedral, Dublin. She became a partner in the business, with the couple overseeing the flourishing of their shop at 79-80 Talbot street. This success allowed them to purchase the department store Clerys & Company on Dublin's main street, O'Connell Street, after it went into receivership in 1941. After buying Clerys, they formed a new limited company, Clery & Co. (1941), in August 1941 and Mary Guiney became one of just two directors, alongside her husband, in a move unusual for the time. Despite the timing of their takeover, during World War II, she was noted as a 'keen businesswoman', with Clerys seeing an increase of 1,000% in turnover. The Guineys invested in the store, installing 42 sales counters over the shop's four floors, as well as a ballroom, two restaurants and three bars. Clerys was credited by some with keeping numerous Irish small suppliers in business during the war, emergency and afterwards, and having a positive effect on the Irish economy more broadly. Clerys became known for its major sales, which took place twice a year. During the first sale, in 1941, O'Connell Street was blocked with traffic, and £100,000 was taken in its first week. Owing to Guiney's strong religious belief, Clerys hosted many charity events, in particular for elderly or isolated Dublin residents. Beginning in 1954, Clerys provided afternoon tea with entertainment for 100 older people. By 1967 the store had over 1,000 employees and was drawing in thousands of customers from across Ireland. Denis Guiney died in 1967, and after contesting some provisions of her husband's will, which had attempted to distribute his shares widely among relatives, Guiney retained control