High-rise timber building construction is becoming increasingly common across the world as construction and woodworking technology advances. The world is moving toward more sustainable development, and products like cross-laminated timber offer economical options for reducing the environmental impact. This chapter contributes to the theory and practice of sustainability assessment and extends the knowledge about high-rise timber buildings. The tallest timber buildings in different countries, such as Mjøstårnet and Treet in Norway and Brock Commons in Canada, are compared across the three dimensions of sustainability (environmental, economic, and social). According to previous research, none of the buildings are at the top in terms of sustainability, but the Brock Commons building in Canada has received the highest rank in all dimensions of sustainability. The issue of fire resistance for timber structures involves a paradox because it is widely recognized that heavy timber construction has outstanding fire resistance in severe fires. Design for burnout may require full or partial encapsulation of timber. Moreover, prefabrication of elements reduces duration and cost of projects. The goal of this chapter is to evaluate and assess the most effective modern high-rise timber buildings from both financial and environmental perspectives.