This talk aims to give an overview of the introduction of the ODF standard and Apache OpenOffice in an Italian public administration with more than 3000 users, addressing briefly the main technical issues and solutions. In particular we will talk about: 1) the configuration of OpenOffice, extended with community developed and custom extensions to help users in the everyday work 2) the interoperability with Sharepoint through the webdav protocol and what we developed in Apache OpenOffice for the correct interaction 3) our extension to simplify picking the right format for file exchange, to answer the users' ubiquitous question "Ok but… should I use ODF to send/share this?”, in relation to our ODF census project in Italy.