The Government has updated the 'How to Rent' booklet which must be issued to assured shorthold tenants.
On 17th January 2018 a new version of the 'How to rent' information booklet was issued.
Where an assured shorthold tenancy in England began on or after 1 October 2015 (or where there's been a replacement tenancy on or after this date) the landlord is unable to give notice under 21 of the Housing Act 1988 unless the tenant has been given a copy of this booklet.
While landlords don't necessarily have to re-issue the new version in respect of current tenancies, they do have to give the tenant the new version if there's been a replacement tenancy since the last version was published (i.e. since 1 February 2016) - at least if they wish to use the section 21 procedure.
It's worth remembering that, as one of the requirements introduced by the Deregulation Act 2015, the booklet will have to be issued to all assured shorthold tenants from 1 October 2018 if the landlord wants to serve a s.21 notice.
See my Section 21 checker tool if you need to decide if a s.21 notice in England is valid. Questions 14 to 19 set out the requirements relating to the 'How to Rent' booklet.