Advanced Terra Testing, Inc  
   USA. Physical testing of soil, rock and geosynthetic designs and materials. General index testing, hydraulic properties and large scale performance testing of geosynthetic products and systems.
   http://www.terratesting.com/

Keantan Laboratories  
   USA. Laboratory and field testing services for environmental and geotechnical projects. Landfill construction quality control and materials testing. Complete programs for geosynthetics and geotechnical testing and investigation.
   http://www.keantanlabs.com/

CRT Laboratories, Inc  
   USA. Independent testing laboratory for polymers, composites, geosynthetics and plastics. Complete testing programs for geomembranes, geotextiles, geonets and grids, and geopipes.
   http://www.crtlabs.com/

Construction Quality Assurance Services, Inc  
   USA. Specialized quality assurance services for municipal, residual, construction, demolition and hazardous waste management facilities. Complete schedule of geosynthetics materials and products tests.
   http://www.cqaservices.com/geotestschedule.htm

Geospec, Ltd  
   UK. Independent laboratory for testing of geosynthetic and geotextile materials. Lists of standard tests for fabrics, membranes, clay liners, composites and grids.
   http://www.geospec.uk.com/

GeoSystems Consultants, Inc  
   USA. Geotechnical engineering and testing laboratory. Standard and specialized procedures for determination of physical and engineering index and performance properties of geotextiles, geomembranes, geosynthetic clay liners and geonets.
   http://www.geosystems.com/

GeoSyntec-SGI  
   USA. Soil-geosynthetic interaction testing services for the geotechnical industry. Tension and seam testing. Compression, direct shear and pullout testing. Masonry block and constant load testing. Also, water property treatability and evaluation. Part of
   http://www.interactionspecialists.com/

GeoTesting Express  
   USA. Laboratory and field tests on rock, soil, landfill design, consolidation and geotechnical projects. Complete programs for testing of geosynthetic materials and products.
   http://www.geotest.com/

H.C. Nutting Co  
   USA. Engineering and testing services for construction, environmental and industrial projects. Laboratory testing services for geosynthetic membranes, fabrics, grids and composites. Also, clay liner and performance evaluation tests.
   http://www.hcnutting.com/

Texas Research International, Inc  
   USA. Independent, multidisciplinary research, development and testing company. Complete testing programs for geosynthetic materials and products.
   http://www.tri-austin.com/

S & ME, Inc  
   USA. Engineering and environmental services for industry and governmental agencies. Testing and quality assurance, and design and specification of geosynthetic materials, products and systems.
   http://www.smeinc.com/

Geotechnical and Structures Laboratory  
   Conducts geotechnical-related research including development, testing, and evaluation projects in soil and rock mechanics, foundation design, embankment design, slope stability. U.S. Army Engineer research and development center.
   http://www.wes.army.mil/SL/gsl.html

AMEC Engineering Pty., Ltd  
   Australia. Independent institute for testing and evaluation of civil engineering materials, including soil, rock, aggregate, concrete and grout. Comprehensive information about available services. On-line job opportunities.
   http://www.ameceng.com.au/