Home Subscriber Server 
Health Service Support 
Hughes Software Systems 
High Speed Serial 
Hydraulic Subsystem Simulator 
Healthcare Services Strategies 
High Speed Steel 
High Stress Strain 
High Service Station 
High-Speed Storage 
History of Science Society 
Compania Transportes Aereos Del Sur 
Hajj Sponsorship Scheme 
Hallermann-Streiff syndrome 
Hallervorden Spatz syndrome 
Hamilton Southeastern Schools 
haplotype sharing statistic 
haplotype sharing statistics 
Hayfield Secondary School 
hazard separation system 
Health Service System 
Health Surveillance System 
Heard Super Swing 
Heat Stable Salts 
Heavy grains, Soyabeans and sorghums 
Heavy-Section Steel 
Helmet Sight Subsystem 
Helmet Sight System 
hemispherical spondylosclerosis 
Heng Shen System