The 4 C's are what I use to map the data journey. Here are the 4 C's:
Data is created. Generally, this is done by people who key in the data manually. Your customers may be data creators if they have to key online applications. Data creators are responsible for creating data as correctly as possible.
The data is also changed. It could be as simple as someone keying a change of address in your database, or changing services for your customers. Data Changers are responsible for keeping the data in line with changes to reality.
This includes data management, regulatory compliance and data quality monitoring and maintenance activities. In the data world, this can also cover parsing, standardising, error correction, de-duplication etc. Controllers are responsible for monitoring and controlling the data. It also covers anyone who has to archive or destroy data to fulfil data regulation.
These are people who view or use the information as part of their job. If you share your information with your customers (account statements etc), they are also included. This also covers Data Protection Act requests for information (UK only). They are responsible for understanding the data, challenging it if they find errors, and making the correct business decisions using it.
These are really snappy ways to remind yourself about the kind of questions you need to ask about a process that you are surveying to understand roles and responsibilities.
All are responsible for process change and maintenance in their areas. All should be consulted and informed about change to the data. The one who should be held Accountable is the colleague who has over-arching control over the whole process. Obviously, if the process spans several departments, accountability can be shared across several function leaders.