The paper discusses the possibility of a small positive cosmological constant (Λ-term) in the universe, based on recent observations of Type Ia supernovae indicating an accelerating universe. It reviews both observational and theoretical aspects of the Λ-term, including its implications for the age of the universe, high redshift supernovae, gravitational lensing, galaxy clustering, and the cosmic microwave background. Theoretical debates focus on mechanisms for generating a small Λ-term, such as spontaneous symmetry breaking and quantum vacuum polarization, which typically produce large values of Λ, leading to the cosmological constant problem. Recent attempts to generate a small Λ-term using field theory or dynamical scalar fields are also discussed. Anthropic arguments for a small Λ-term are briefly reviewed. The paper also explores the theoretical issues of vacuum fluctuations and the cosmological constant, as well as the role of Λ in models of structure formation and the universe's future. Observational data from the cosmic microwave background, galaxy clustering, and supernovae support a flat universe with Λ ≈ 0.7. The paper concludes that the case for a positive Λ-term should be taken seriously, given the growing body of evidence and the potential relationship between a small Λ-term today and a large Λ-term driving inflation in the early universe.The paper discusses the possibility of a small positive cosmological constant (Λ-term) in the universe, based on recent observations of Type Ia supernovae indicating an accelerating universe. It reviews both observational and theoretical aspects of the Λ-term, including its implications for the age of the universe, high redshift supernovae, gravitational lensing, galaxy clustering, and the cosmic microwave background. Theoretical debates focus on mechanisms for generating a small Λ-term, such as spontaneous symmetry breaking and quantum vacuum polarization, which typically produce large values of Λ, leading to the cosmological constant problem. Recent attempts to generate a small Λ-term using field theory or dynamical scalar fields are also discussed. Anthropic arguments for a small Λ-term are briefly reviewed. The paper also explores the theoretical issues of vacuum fluctuations and the cosmological constant, as well as the role of Λ in models of structure formation and the universe's future. Observational data from the cosmic microwave background, galaxy clustering, and supernovae support a flat universe with Λ ≈ 0.7. The paper concludes that the case for a positive Λ-term should be taken seriously, given the growing body of evidence and the potential relationship between a small Λ-term today and a large Λ-term driving inflation in the early universe.