It aims to give parents of babies due, or children placed for adoption, on or after this date greater flexibility in how to share the care of their child in the first year following birth or adoption.
Parents will be able to share a pot of leave and can decide to be off work at the same time and/or take it in turns to have periods at home to look after the child.
You can find further guidance in a detailed code of conduct produced by Acas.
How eligibility and payment are calculated is very complex and the Department of Business, Innovation and Skills have produced a helpful online calculator.
The move follows the introduction last October of the right for fathers and partners to take unpaid time off work to accompany expectant mothers to up to two antenatal appointments.
The Children and Families Act also introduced a new right for adoptive parents effective from April 5 with the primary adopter able to take paid leave five times – to meet the child they are going to adopt or for other meetings arranged by the social worker. The secondary adopter is entitled to unpaid time off for up to two appointments.