Hi JWTeasdale
If you have either the Essential or Plus products you will be able to set up the multicurrency from within the settings.
You will have to select the cog icon in the right hand corner of the screen, select account and settings, select advanced, click into the currency section and select Multicurrency, read and select the disclaimer and select save.
When creating a supplier or a customer that would like to use a foreign currency you will have to, when creating a supplier select the currency from the drop down menu in the 'I pay this supplier with' section and when creating a customer you will have to select the 'payment and billing' tab and in the 'This customer pays me with' use the drop down menu and select the currency.