Army Social Services

Red Cross: Everyone 
Linking Military Families During an Emergency 
Connecting Families with Local Community Resources 
Providing Resiliency Training 
Supporting Wounded Warriors and Military Hospital
http://www.redcross.org/what-we-do/support-military-families

Army One Source Website
Developed in the last couple of years because of the lack of one access point for services.  This should provide many options for services.
Army One Source: Service Locator

Moral, Welfare and Recreation (MWR) Service members, family members and in some cases civilian contractors. Governed by AR215-1c and DoD Instruction 1015.10
Most social services fall some where under MWR. Military libraries, bowling allies, movie theaters, arts and crafts buildings, and similar facilities are most directly associated with MWR.
Better Opportunities for Single Soldiers (BOSS) soldiers only
Organization for the better treatment of Single Soldiers. Single Soldiers tend to get the raw deal when it comes to extra task and duty assignment due to not having family members. Falls under MWR.

Army Community Serves (ACS) Soldiers, family members and in some cases civilian contractors. Governed by AR 608-1
Provides a wide range of services that are dependent on local resources. Some programs that will be found at most if not every post/installation is the Lending closet,Family Advocacy (FAP),Domestic Violence & Child Abuse,Sexual Assault Prevention/Response, New Parent Support (NPSP),Survivor Outreach Services (SOS),Exceptional Family Member (EFMP), Army Family Team Building (AFTB), Children & Deployment

Army Emergency Relief (AER): Active Duty Army soldiers
 "Helping the Army Take Care of Its Own."
Mostly Financial Assistance. This website has links to other organizations that may be helpful.
http://www.aerhq.org/dnn563/

Family Readiness Group (FRG) family members typically geared towards dependents and close family members Governed by Army Regulations
Group that works as a support group or source of information. Find more information at the following website  https://www.armyfrg.org/skins/frg/home.aspx

This is just a brief overview of  Army Social Services.  Let me know about any agency or service that you want to share with others.