The ever-expanding world of IoT and IIoT devices necessitates a robust and adaptable security framework to safeguard these interconnected systems. This chapter outlines the core principles for building such a framework, emphasizing proactive and continuous protection strategies for vulnerability analysis, malware detection, and anomaly detection. The framework foundation lies in conducting thorough risk assessments. By identifying potential vulnerabilities in devices, networks, and protocols, we can prioritize mitigation efforts and the use of secure protocols like TLS (transport layer security) and DTLS (datagram transport layer security) for encrypting data transmission, protecting sensitive information from unauthorized access. Anomaly detection systems identify deviations from normal behavior, while intrusion prevention systems (IPS) actively block malicious network activity. However, security cannot be an afterthought. This chapter emphasizes the importance of integrating security considerations throughout the development lifecycle of IoT/IIoT devices.