Purpose of Review <p>This review aims to synthesize recent advances in the understanding of interstitial cystitis/bladder pain syndrome (IC/BPS) pathophysiology, focusing on mechanisms underlying its heterogeneity and emerging diagnostic and therapeutic insights.</p> Recent Findings <p>Recent studies highlight distinct bladder-centric and systemic phenotypes of IC/BPS. Key mechanisms include epithelial barrier dysfunction, mast cell–mediated inflammation, neurogenic sensitization, and dysregulation of stress-related neuroendocrine pathways. Alterations in urinary and gut microbiota further suggest a gut–bladder axis contributing to chronic inflammation and pain. Novel biomarkers such as NGF, VEGF, and antiproliferative factor may aid in disease stratification, while emerging therapies targeting immune modulation, microbiome restoration, and regenerative repair show promising results.</p> Summary <p>IC/BPS is a multifactorial condition involving interrelated immune, neural, and microbial pathways. Recognition of distinct phenotypes and molecular mechanisms supports a shift toward precision medicine, enabling more individualized and mechanism-based management strategies.</p>