SALT

Strategic arms limitation talks

SAO

Smithsonian Astrophysical Observatory

SBA

Small Business Administration

SBIC

Small Business Investment Companies

SCS

Soil Conservation Service

SEA

Science and Education Administration

SEAN

Scientific Event Alert Network

SEATO

Southeast Asia Treaty Organization

SEC

Securities and Exchange Commission

SIPC

Securities Investor Protection Corporation

SITES

Smithsonian Inst. Travelling Exhibition Service

SLS

Saint Lawrence Seaway Development Corp.

SPARS

Women's Coast Guard Reserves (from Coast Guard motto "Sempter Paratus - Always ready")

SSA

Social Security Administration

SSIE

Smithsonian Science Information Exchange, Inc.

SSS

Selective Service System

Stat.

United States Statutes at Large