In connective tissue diseases, especially systemic lupus erythematosus and Sjögren's syndrome, diverse neurological symptoms and syndromes involving both the central and peripheral nervous system can occur at any stage of the disease. The pathogenesis is diverse. Prevalence figures in the literature vary considerably and the causal relationships are often uncertain. Very often connective tissue diseases must be considered in the differential diagnosis of conditions manifesting with unclear neurological symptoms. Both rheumatologists and neurologists should be familiar with the main neurological signs, symptoms and complications of connective tissue diseases and should recognize the importance of diagnostic testing.