Acoustics is a discipline that affects the quality of every building. This ranges from the expected: performing arts and cultural centres, to the unexpected: offices, condo towers, commercial, and institutional buildings. Acoustics is one of the few areas with truly multi-disciplinary impact, affecting architectural, mechanical, electrical, and structural equally. This lecture will discuss, in detail, the key acoustical design parameters that help create successful buildings, positive user experiences, and accessible spaces. Case studies presented will demonstrate a wide variety of acoustical challenges and straightforward approaches and solutions that can be employed by the designer.