Pen Test Partners (PTP) is a UK-based cybersecurity services firm offering a broad portfolio of offensive security, detection, response, and compliance services to organizations across multiple industries including finance, healthcare, retail, and transport. Their testing and simulation services include penetration testing, Pen Testing as a Service (PTaaS), red teaming (including regulated frameworks such as CBEST, GBEST, STAR-FS, and TIBER), purple teaming, attack surface assessments and management, cloud testing, physical security testing, OT/ICS/IIoT security testing, transport systems testing, and artificial intelligence testing. On the detection and response side, PTP provides incident response, incident response retainers, digital forensic investigations, dark web OSINT assessments, exposure and identity risk assessments, managed detection and response, and compromise assessments. Their advisory and improvement services encompass security architecture review, secure software development lifecycle (SDLC) consulting, cloud configuration best practices, cyber security gap analysis, maturity assessments, security training, virtual CISO services, third-party vendor assurance, and a proactive password auditing tool (PAPA). PTP also offers compliance support including Cyber Essentials, Cyber Essentials Plus, PCI DSS ROC Level 1 assessments, PCI SAQ assessments, and formal certification preparation. The firm is notable for published research into IoT, connected vehicles, aviation systems, GPS spoofing, and industrial control systems, with frequent media coverage from outlets such as Reuters, BBC, The Register, and Wired.