*3.2. Primary Service Provider*

A second challenge in implementing the RBM is the use of a primary service provider (PSP), rather than having a host of different providers from different disciplines working with the child [35,41]. Many early intervention cultures, worldwide, are very discipline driven, with a view that more is better. In Poland, for example, sensory integration therapists are separate from occupational therapists, and, in most other countries, psychologists play a much bigger role in early intervention than they do in the U.S. In Spain, they have psychometricians, a discipline that does not even exist in some other countries. In Paraguay, they have "early intervention professionals" who are different from teachers, therapists, and so on. So, when implementers try to organize a PSP approach, they meet much resistance. When a primary service provider cannot be used, one provider serves as the *comprehensive* service provider, attending to all child and family needs [42].
