### §2.1.1 Binding interfaces

Role base bindings may involve classes and/or interfaces. An interface defined as a member of a team is a role interface and may therefore have a `playedBy` clause. Also the type mentioned after the `playedBy` keyword may be an interface.

##### Implementation limitation:

The language implementation as of OTDT version 2.0 imposes one particular restriction when binding a role to a base interface: A role binding to a base interface may not contain any callin bindings (§4).