This dissertation is a detailed study entitled "Architectural and Structural Design ofThree-Storey Modern Market Building: Case Study of Kisii Central District." The object in question is a three-storey modern market building measuring 52.153 length x42.995 width with main features like balconies, washrooms, bedrooms, verandahs, and kitchens. Each floor stands at a height of 3.80 m. The structural analysis applied general principles in civil engineering to carefully design key items such as beams, slabs, columns, foundations, and stairs. The longitudinal had a depth of 800 mm and a width of 300 mm, with a wing width of 907 mm using Ø40 mm reinforcement bars both on the upper and lower sides. Slabs were divided into three categories, namely continuous and discontinuous. Slabs had 15 cm thickness and were supported by Ø12 mm reinforcement bars. Columns of the mix contained Ø40 mm bars with Ø8 mm links at 144 mm centre to centre. The bearing capacity Pb = 400 KN/m 2 was used for the foundation design, which gave the foundation dimensions 4000*4000*500 mm, reinforced with Ø20 mm bars as the significant reinforcement. Stairs providing access between the floors were constructed with a going of 305 mm and a riser of 160 mm. The flights rose 200 cm with a pitch of 29.53 0. The reinforcement included Ø16 mm bars at the bottom and Ø8 mm bars at the top. This dissertation presents a detailed study of the structural details involved in the construction of a three-story apartment building. It gives insight into the best construction practices through careful analysis and design, considering a context that differs from any other: the Kisii Central District.