Chronic inflammatory demyelinating polyneuropathy (CIDP) is a chronic neuropathy characterized by symmetrical proximal and distal weakness, with large-fiber sensory loss, impaired balance, and areflexia. This condition is often underdiagnosed due to the frequent absence of these classical clinical features as well as abnormalities that arise during confirmatory tests. Current diagnostic tests involve the measurement of cerebrospinal fluid protein levels, nerve biopsy, electrodiagnostic testing, and treatment response. Due to the clinical heterogeneity of the condition and a lack of a consistent confirmatory test, a variety of diagnostic criteria were developed. At least 14 different sets of diagnostic criteria have been proposed that each have varying diagnostic sensitivities. Although the diagnostic tests used within these criteria are useful, they individually offer evidence to support, rather than definitively confirm, the diagnosis of CIDP. Currently, there is no biomarker that can reliably identify all patients with CIDP, but it is evident that such a biomarker is urgently needed to ensure effective disease management.