Insects provide indispensable ecosystem services that sustain biodiversity, agricultural productivity, and ecological resilience. This literature explores the multifaceted roles of insects in ecosystem functioning, emphasizing pollination, decomposition, natural pest control, and aquatic ecosystem maintenance. Pollinators such as bees, butterflies, and flies contribute significantly to global food security and plant reproduction, while decomposer and predatory insects enhance soil fertility and pest regulation. The chapter highlights how insect diversity underpins ecosystem stability and how its decline poses severe risks to food systems and environmental health. It examines the growing threats from habitat loss, monoculture farming, pesticide overuse, climate change, and invasive species, which collectively disrupt ecological balance and diminish pollination efficiency. Additionally, it discusses the innovative potential of bio-inspiration derived from insect physiology and behavior in advancing sustainable technologies and climate adaptation. Current global initiatives, including those led by IPBES and FAO, are also reviewed for their efforts in promoting insect conservation and policy integration. The chapter concludes by emphasizing the urgent need for ecosystem-based management, landscape diversification, and strengthened institutional support to safeguard insect-mediated services essential for global sustainability, climate resilience, and human well-being.