Version 4.2 includes additional and updated guidance. This document outlines The Standard Response Protocol (SRP), and offers guidance on incorporating this protocol into a school safety plan for critical incident response within individual schools in a school district. This document intends to provide basic guidance with respect to local conditions and authorities. The only mandate presented is that districts, agencies, and departments, retain the "Terms of Art, which are actions," and "Directives" defined by this protocol. The SRP is not a replacement for any school safety plan or program; it is a classroom response enhancement for critical incidents, designed to provide consistent, clear, shared language and actions among all students, staff, and first responders. As a standard, SRP is being adopted by emergency managers, law enforcement, school and district administrators, and emergency medical services across the country.