This page is the reading order, not a second glossary. Each concept is one or two paragraphs. The full definition lives on its [Early Intervention](/early-intervention) page. Do not copy those definitions here.

## Referral [#referral]

A referral is how a child enters New York Early Intervention. The official date starts the 45-day clock to the first plan meeting. Read [What is a referral?](/early-intervention/referral) and [What is the 45-day clock?](/early-intervention/forty-five-day-clock).

## Multidisciplinary Evaluation [#multidisciplinary-evaluation]

The Multidisciplinary Evaluation is the team evaluation that informs eligibility and the first plan. Two or more qualified personnel from different disciplines assess the five domains. Read [What is a Multidisciplinary Evaluation?](/early-intervention/multidisciplinary-evaluation).

## Eligibility [#eligibility]

A child is eligible through a diagnosed condition or through a documented developmental delay that meets New York's thresholds. Tiny records the municipality's determination; it does not invent a parallel one. Read [How does eligibility work?](/early-intervention/eligibility).

## Individualized Family Service Plan [#individualized-family-service-plan]

The Individualized Family Service Plan is the written plan for an eligible child and family. It is not a school-age special education document. Read [What is an IFSP?](/early-intervention/ifsp).

## Service Authorization [#service-authorization]

A Service Authorization is permission for one service, to one provider, for a stated period. There is no separate notice object. Read [What is a Service Authorization?](/early-intervention/service-authorization).

## Session note and service log [#session-note-and-service-log]

Every session produces two documents: the provider-signed session note and the parent-signed service log. They are not interchangeable. Read [What is a session note?](/early-intervention/session-note) and [What is a service log?](/early-intervention/service-log).

## Transition [#transition]

Transition is the planned move out of Early Intervention as the child approaches age three. Not every exit is a transition. Read [What is transition?](/early-intervention/transition).

## HIPAA [#hipaa]

Session notes, service logs, plans, and state-system exchanges carry protected health information. HIPAA is the floor; New York retention adds more. Read [How does HIPAA apply?](/early-intervention/hipaa).