title: Multi-Currency Best Practice & Implementation
body: <p>I'm finding it difficult to find any discussion on best practices for dealing with multiple currencies. Can anyone provide some insight or links to help?</p>
  
  <p>I understand there are a number of ways to do this - either transactionally where you store the value entered as is, or functionally where you convert to a base rate. In both cases the exchange rate is needed to be stored that covers that transactions time for each currency that it may need to be converted to in the future.</p>
  
  <p>I like the flexibility of the transactional approach, which allows old exchange rate info to be entered at a later date, but probably has more overhead (as you have to store more exchange rate data) than the functional approach.</p>
  
  <p>Performance &amp; Scalability are major factors. We have (all .net) a win &amp; web client, a reports suite and a set of web services that provide functionality to a database back-end. I can cache the exchange rate information somewhere (e.g. on client) if required.</p>
  
  <p><b>EDIT: I would really like links to some documents, or answers that include 'gotchas' from previous experience.</b></p>