Systemic lupus erythematosus (SLE) is a multisystem disease with varied manifestations and course. Variation in presentation among patients, and within the same patient, there may be varied manifestations over time. It has been difficult to measure the extent of disease activity accurately. Several investigators and groups have developed definitions of disease activity and methods to measure it. Consequently, there are currently several instruments to measure disease activity as well as damage in patients with SLE.This review covers currently available evidence on measures of disease activity in SLE. It discusses potential avenues for further development of new measures and the refinement of existing tools to improve disease activity measures in research and clinical care settings.: Given the complexity and heterogeneity of the disease, further work and tools are needed to assess disease activity better. Organ-specific measures for cutaneous, renal, and joint manifestations are needed for a detailed assessment of disease activity in conjunction with the use of disease generic tools (e.g., SLEDAI). New tools such as the SLE Disease Activity Index-Glucocorticoid Index (SLEDAI-2KG) incorporating glucocorticoid doses to describe disease activity, SLE-DAS and SLEDAI-2K RI-50 to record partial improvements could also be helpful.