The outline  of this program is from the website http://www.masspartnership.com/provider/index.aspx?lnkId=contacts.ascx&imgID=Prov_ImportantContacts.jpg#emergencyServiceProviders.  Here is the description of their services.

Emergency Service Providers
Every ESP provides behavioral health crisis assessment, intervention and stabilization services, 24 hours per day/7 days per week/365 days per year, through 4 service components: Mobile Crisis Intervention (MCI) services for youth, adult mobile services, ESP community based locations, and community crisis stabilization (CCS) services for ages 18 and over. The operating hours for the ESP community based locations are noted in the ESP Directory. Mobile Crisis Intervention services for youth are available 24 hours per day/7 days per week. The operating hours for adult mobile services are 24 hours per day/7 days per week: during this time period, mobile services will be available from 7 a.m. to 8 p.m. at any/all locations, and from 8 p.m. to 7 a.m. this service will be available in residential programs and hospital emergency departments. CCS services are available 24 hours per day/7 days per week and can be accessed through the ESP.

Very helpful for you to have on hand and to give your clients is the 24 hour number for their area:

Here is the  web site to the directory of these services:

http://www.masspartnership.com/provider/pdf/ESP-MCIDirectoryfinal041210.pdf