This chapter analyses Malaysia’s substantive terrorism offences and sentencing practices, focusing on expansive criminalisation and proportionality. It examines how preparatory acts, intent-based offences, and broad statutory definitions have widened the net of criminal liability. Through legal analysis, the chapter questions whether sentencing outcomes reflect culpability and harm, or whether they are driven by preventive logic and deterrence imperatives. It highlights the risks of disproportionate punishment and the erosion of foundational criminal law principles.