Dear colleagues: Thanks for all your useful information, in this time I would like to ask about the recommended period of time to test a new system (Financial area) to be put in Production mode. I know this completely depends on the kind of system as well as the volume of data which will be managed but talking about a financial system where we have lots of transactions and data I think the recommended time to test would be from 4 to 6 months but I am not quite sure. Considering a system which is in production, it is recommended to use the one which is new parallel in order to catch the errors, isn´t it? I´ll appreciate your answers as well as your comments. Thanks!