The IYENGAR Yoga Association (UK)
www.IYENGARyoga.org.uk 

Eliptisoft Ltd (Web Site and Software Consultancy)
www.eliptisoft.co.uk

The IYENGAR Yoga Institute (Maida Vale)
www.iyi.org.uk
The Official International BKS IYENGAR Site
www.bksiyengar.com 
The Long Ditton Yoga Centre
www.yogadham.co.uk

The Bhavan Centre (West Kensington)
www.bhavan.net

Yoga Loka - IYENGAR Yoga in Richmond and Kew
www.yogaloka.com

John Shirbon teaches at some other venues on a weekly basis. Notably:

The Bhavan  4a Castletown Road  West Kensington
London W14  Tuesdays 6.30 to 8pm £6 per class (drop in, no need to book) see link above

Virgin Active Health Club South Wimbledon (Membership required) T el 0208 544 0111 for times and address