15. Other intangible assets

Computer
software
£000
Patented and
unpatented
technology
and know-how
£000
Customer
contracts and
relationships
£000
Total
£000
Cost
At 1 May 20151,9152,86585,63090,410
Effects of exchange rate changes3563,8443,885
Additions27384357
Transfers150150
At 30 April 20162,3732,95589,47494,802
Accumulated amortisation
At 1 May 20151,4252,01510,34313,783
Effects of exchange rate changes53233241
Charge for the year2409313,14013,473
Disposals11
At 30 April 20161,6712,11123,71627,498
Net book amount at 30 April 201670284465,75867,304
Cost
At 1 May 20141,3872,8307,37711,594
Acquisition of subsidiaries (Note 28)3763482,29982,709
Effects of exchange rate changes(25)(4,046)(4,071)
Additions1771178
At 30 April 20151,9152,86585,63090,410
Accumulated amortisation
At 1 May 20141,3201,9323,3076,559
Effects of exchange rate changes10251261
Charge for the year95836,7856,963
At 30 April 20151,4252,01510,34313,783
Net book amount at 30 April 201549085075,28776,627

Transfers relate to intangible assets transferred from assets under construction (PPE) to computer software during the year.

Acquisition of subsidiaries in the prior year

Customer contracts and relationships include intangible assets acquired through business combinations as disclosed in note 28. Further details regarding individually material intangible assets have not been included since these are deemed to be commercially sensitive.