Manufacturing systems are increasingly subject to changes. Information and knowledge are therefore essential for the ability to predict potential problems. Results are presented from 16 companies with focus on how production requirements, as perceived from production personnel´s perspective, are considered when changes are planned and realized. A gap between production and information system development is identified according to less competence and authority within the latter area. To improve preparedness, information access in a structured but rapid way, not always dependent on individuals or formalized meetings, is desired. Even though there are advantages with formalized information transfer through e.g. structured work procedures, it is not obvious that user requirements in production are fulfilled. This indicates a need of further research on efficient information system strategies regarding the degree of formal and/or informal information transfer.