Ankylosing spondylitis (AS) and spondylarthritis (SpA) are generally observed in young male patients but can be diagnosed in the elderly. These cases correspond to late-onset or late-diagnosed AS or SpA. The clinical presentation may be either typical axial disease with a more severe illness compared with young-onset disease, or peripheral oligoarthritis of the lower limbs with pitting oedema (late-onset peripheral spondylarthropathy). New criteria for axial SpA including MRI-determined modifications of the sacroiliac joints may help the clinician with diagnosis. The treatment options for late-onset/-diagnosed AS include the same drugs as those taken by patients with young-onset AS, i.e. NSAIDs, sulfasalazine and anti-tumour necrosis factor (TNF)-alpha agents. Anti-TNFalpha agents are very effective drugs in young-onset AS and SpA. However, the effectiveness and safety of this drug class has not been specifically evaluated in elderly AS/SpA patients, and caution is therefore required with use of these drugs in elderly patients with co-morbidities and/or polypharmacy. In particular, careful evaluation for the risk of infection and cardiovascular events is recommended before initiating anti-TNFalpha agents in this age category. However, safety data from elderly patients with rheumatoid arthritis seem reassuring. With the increasing life expectancy and the new diagnostic modalities for axial (and peripheral) SpA, it is likely that the number of patients (diagnosed) with late-onset AS/SpA will increase. Thus, the clinician must be familiar with the clinical characteristics and particularities of this group of inflammatory rheumatic diseases.