Urothelial carcinoma, the most common malignancy of the urinary tract, frequently presents as non-muscle-invasive bladder cancer (NMIBC), comprising approximately 70–75% of bladder cancer cases. NMIBC encompasses papillary tumors confined to the mucosa (Ta), lamina propria-invasive tumors (T1), and carcinoma in situ (CIS), a high-grade intraepithelial lesion with significant malignant potential. Risk factors include smoking, occupational exposure to carcinogens, family history, dietary influences, metabolic factors, prior radiation, and specific drug exposures. Accurate diagnosis relies on patient history, hematuria evaluation, cystoscopy, imaging, and urine cytology, with cystoscopic biopsy remaining the gold standard. Management is centered on transurethral resection of bladder tumors (TURBT), which serves both diagnostic and therapeutic purposes. Adjuvant intravesical therapy is essential, with immediate postoperative instillation of chemotherapeutic agent reducing early recurrence. Bacillus Calmette–Guérin (BCG) remains the most effective agent for intermediate- and high-risk NMIBC, significantly lowering recurrence and progression rates when given with maintenance schedules. Patients with BCG-unresponsive or very high-risk tumors should be considered for early radical cystectomy, which offers superior disease-specific survival compared to delayed surgery. Surveillance is critical due to the high recurrence and progression potential of NMIBC. Follow-up protocols are risk-stratified, with cystoscopy and cytology forming the mainstay of monitoring. Emerging imaging modalities such as VI-RADS MRI and novel urinary biomarkers show promise but require further validation. Preventive strategies include smoking cessation, hydration, and dietary modifications, though no chemopreventive agents have consistently demonstrated benefit. Overall, NMIBC represents a heterogeneous disease requiring individualized management based on risk stratification. A combination of meticulous resection, optimized intravesical therapy, timely surgical intervention, and structured surveillance forms the cornerstone of improving long-term outcomes in affected patients.