Just to add in an amendment to my above post (sorry, occurred to me late!)
...The above link to the EU-OPS 1 is old, and therefore factually my hasty links were slightly misleading. There were several areas for concern after its publication which EASA sought to address. Notably Moebus Aviation's report looked in depth at certain concerns:
http://www.easa.europa.eu/rulemaking...l%20Report.pdf
...and then EASA published an NPA which explained how they would amend some, but not all of the issues raised:
http://easa.europa.eu/rulemaking/doc...%202010-14.pdf
I will warn you, whilst the former is easy-ish going, the latter is not for the faint hearted.