Daniel [née Lee], Joyce Mary (1890–1985), campaigner for birth control, was born on 10 May 1890 at Redland House, north Malvern, Worcestershire, the third of three daughters of Walter Lee, a Congregational minister, and his wife, Alice Amelia Hyrons. She was educated at Milton Mount College, in Kent, and was employed as a secretary in banks in Worcester and Birmingham until she married Archibald Daniel (b. 1874/5), son of William Lewes Daniel, official receiver of bankruptcy. They married on 23 April 1918 and she moved to Pontypridd where he was a solicitor. They had two sons, Noel (b. 1919) and Tony (b. 1922). She was also guardian to her husband's son, Russell, whose mother had died in childbirth.

In 1930 Joyce Daniel, as a result of her involvement delivering maternity parcels for the Lord Mayor's Distress Fund, was approached by Janet Chance, the founder of the Abortion Law Reform Association, whose attempts to raise money from doctors, councillors, magistrates, and other important local figures to establish a birth control clinic in Pontypridd had failed. Joyce Daniel invited the wives of these officials who did not 'care to be mixed up in it' (Family Planning Association archives) to a meeting held in her own sitting room. This all-woman meeting resolved to set up and finance the clinic and use their domestic influence to overcome their husbands' reluctance. An application to the local authority health committee for permission to hire rooms in the maternity and child welfare premises was also refused, but the decision was reversed after Daniel visited each councillor in person.

Joyce Daniel's resourcefulness and determination did not go unnoticed. Following the government's decision in 1930 to allow local authorities to provide birth control advice to women for whom further pregnancy was deemed detrimental to their health (memo 153/MCW), Daniel was made local correspondent and later area organizer for the National Birth Control Association (NBCA); this was an amalgamation of various birth control associations and later became the Family Planning Association. Daniel proved to be active, dedicated, and successful. The executive committee minutes of the NBCA frequently noted the amount of unpaid overtime she put in. She approached councils, medical officers of health, health committees, and maternity committees, forced a discussion of birth control on to local authority agendas, and persevered, frequently revisiting areas where she did not meet with immediate success. Such pressure was essential as the government did not publish the new permissive memo, sending it out, at first, only to local authorities who asked for it. Daniel reported finding the memo 'lying forgotten in council pigeon holes' (Western Mail). In September 1932, after only two years' activity, she had succeeded in increasing the number of clinics in south Wales from one to eight. By 1939 thirteen authorities had set up clinics (Aberdâr, Barry, Caerphilly, Gelli-gaer, Llanelli, Llantrisant and Llantwit Fardre, Mountain Ash, Ogmore and Garw, Penarth, Pontardawe, Pontypridd, Port Talbot, and Rhondda). Maesteg was in the process of setting one up, Merthyr had set up a clinic in co-operation with the NBCA, and Glyncorwg urban district council had made arrangements to send women to the clinic at Pontypridd. She had also established a voluntary clinic in Pontypool. The number of clinics run by local authorities in south Wales was significant and attests to the success of Daniel's campaigns. In 1939 thirteen of the seventy-nine local authority birth control/gynaecological clinics in Great Britain were in south Wales. Elsewhere clinics tended to be set up by voluntary associations and received varying degrees of support from local authorities.

Politically Conservative (she was scornful of the Labour Welsh), religiously active (she had a family pew in the local United Reformed church), and with an air of social superiority, Daniel's motives for her involvement in the birth control movement stemmed more from the traditions of Victorian philanthropy than from radical proto-feminism. A 1970s history of general practice in south Wales described her as being saddened by the plight of mothers worn out by successive pregnancies and eager to give them an alternative solution to backstreet abortions. There is no evidence, however, that she shared any of the eugenic motives associated with many supporters of the birth control movement. She was opposed to abortion and refused to remove the words 'married women only' from clinic advertisements in the 1950s despite pressure from the central Family Planning Association (FPA). 'I kept having to tell them … that with the Roman Catholics on one side and the Nonconformist Conscience on the other I just could not do it' (Western Mail).

Daniel remained active in the NBCA for thirty years. One FPA worker remembered her as 'tall, autocratic looking and very positive. The people who were associated with her were absolutely devoted to her, and in awe, as she had obviously fought some great battles' (private information). It is for this persistence and formidableness that she is primarily remembered; stories were even told of her personally confronting violent husbands who were opposed to their wives' attending a birth control clinic. Joyce Daniel died on 29 January 1985 of bronchopneumonia during a visit to her niece, at 292 Avery Hill Road, Eltham, London. She was cremated in Kent and her ashes were buried in Glyntaf cemetery in Pontypridd.