White Badger Group, Inc.
- Providers of penetration testing, vulnerability assessment, consulting, and educational services.
- http://www.whitebadger.com

Signal Networks Ltd
- Provides ethical hacking, assessments and security services.
- http://www.signalnetworks.co.uk/

Madison Gurkha,
- A consultancy firm based in The Netherlands providing penetration testing and auditing and subsequenet threat mitigation services.
- http://www.madison-gurkha.com/

ProCheckUp Limited
- MasterCard SDP compliant penetration and application security testing firm based in the United Kingdom. Offers articles, service information and contact details.
- http://www.procheckup.com/

Hacksafe Pty Ltd
- Provides penetration testing and vulnerability assessment services, virus testing services, education and training.
- http://www.hacksafe.com.au/

Remote Vulnerability Assessment Solutions, Inc.
- RVASI provides services and solutions globally. Specializes in web application vulnerability assessments.
- http://www.rvasi.com/

Ilion Security SA
- Ethical hacking and computer security training. Geneva, Switzerland.
- http://www.ilionsecurity.ch/

Covert Systems
- Specializes in network penetration analysis, systems configuration and managed services.
- http://www.covertgroup.net/

NTA Monitor Ltd.
- Specializes in perimeter and penetration testing. Offers facts sheets, and security bulletins. Based in the UK.
- http://www.nta-monitor.com/

Greyhat, LLC.
- Specializes in penetration testing, vulnerability assessments, network, commerce and business security, intrusion detection and response, risk mitigation, and consulting services.
- http://www.greyhat.com/

SecureCom UK Limited
- Provides penetration and wireless security testing, vulnerability assessments, social engineering and full security audits. Based in South England.
- http://www.securecomuk.com/

Tiburon Enterprises LLC.
- Services include vunerability and compliance assessments, penetration testing, and executive advisory services.
- http://www.tiburon-ent.com/

Data Cog Corporation Limited
- Penetration testing and other security consulting services, and IDS solution. Service and product information, company news and contact details.
- http://www.datacog.com/

ITamon
- Provides services for security, investigation, web security and ICT awareness. Specializes in penetration testing.
- http://www.itamon.com/

Sec-Tec Limited
- Provides product independent digital security services, specialising in penetration testing, technical training and core security consulting. Located in London, England.
- http://www.sec-tec.co.uk/

Phoenix IT Solutions, LLC:
- Offers several security auditing packages include risk assessment and penetration testing. Based in Washington, DC, USA
- http://phoenixitsolutions.com/auditing.htm

mwr InfoSecurity
- Provide penetration testing, web application testing, vulnerability assessments, continuous security verifications, wireless security testing, firewall testing, security policy development, and CESG CHECK.
- http://www.mwrinfosecurity.com/

Tevora Business Solutions
- An Irvine, California USA based company that provides assesment, audit, and vulnerability testing as well as firewalls, vpn solutions, and managed services.
- http://www.tevora.com/

Pure Hacking Pty Ltd
- Dedicated penetration testing services focusing on network application and Internet security.
- http://www.purehacking.com/

Digital Defense Inc.
- Offers a range of penetration testing and vulnerablity assement services as well as policy development and security management.
- http://www.cusecure.com/

Acros Security
- Slovenian business dedicated to locating security problems in network systems software and hardware.
- http://www.acros.si/

E-Commerce Security Consultants
- Providing varying levels of network security audits.
- http://www.ecsc.co.uk/