Modern systems face security challenges at every layer of the stack, from user authentication to machine learning and software execution. In this talk, we present three lines of research aimed at strengthening defenses. First, we discuss advances in password deception, including honeyword generation and breach detection frameworks that address practical weaknesses in existing approaches. Next, we examine the security of machine learning-based services, highlighting vulnerabilities such as membership inference, model inversion, and adversarial text generation, and analyzing why many attacks fail in realistic settings. Finally, we introduce VALIDATE, a novel framework for binary-level security assurance, designed to ensure that applications compiled with memory-safe programming languages (e.g., Rust) retain their protective checks and remain tamper-free before execution. Together, these perspectives underscore the need for holistic, multi-layered security that anticipates and disrupts adversaries at multiple points of attack.