A study of neutral-current four-fermion processes is performed, using data collected by the L3 detector at LEP during high-energy runs at centre-of-mass energies 130–136, 161 and 170–172 GeV, with integrated luminosities of 4.9, 10.7 and 10.1 pb⁻¹, respectively. The total cross sections for the final states ℓℓℓ′ℓ′ and ℓℓqq (ℓ, ℓ′ = e, μ or τ) are measured and found to be in agreement with the Standard Model prediction.