nctional neurological disorder (FND) both co-exists with and closely mimics many well-recognized neurological conditions. These include migraine, multiple sclerosis, dementia, Parkinson’s disease, stroke, and epilepsy. This dual relationship creates significant clinical challenges. FND may present alongside these disorders as a comorbidity, or its symptoms may resemble those of other neurological diseases, making an accurate diagnosis essential. FND is also frequently associated with a range of other co-morbidities, such as neurodevelopmental conditions (including autism spectrum disorder and ADHD), postural orthostatic tachycardia syndrome (POTS), autonomic dysfunction, hypermobility syndromes, depression, anxiety, and post-traumatic stress disorder (PTSD). These conditions can influence symptom presentation, complicate assessment, and impact treatment strategies. Recognizing and differentiating FND from other neurological and systemic conditions is crucial for ensuring that patients receive the most appropriate and effective care. Misdiagnosis can lead to unnecessary investigations or treatments, while missed co-morbidity may result in incomplete management.