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We consider the derivation and rigorous justification of models for thin linearly elastic plates using mixed variational principles. We consider an isotropic, homogeneous, linearly elastic plate occupying the region Pt = Ω × (−t/2, t/2), with Ω a smoothly bounded domain in R2 and t ∈ (0, 1]. We denote the union of the top and bottom surfaces of the plate by ∂P±t = Ω × {−t/2, t/2} and the lateral boundary by ∂PLt = ∂Ω × (−t/2, t/2). We suppose that the plate is loaded by a surface force density g: ∂P±t → R3 and a volume force density f: Pt → R3, and is clamped along its lateral boundary. The resulting stress σ ∗ : Pt → R3×3sym and displacement u ∗ : Pt → R3 then satisfy the boundary-value problem Aσ ∗ = ε(u∗), −div σ ∗ = f in Pt, σ∗n = g on ∂P±t, u ∗ = 0 on ∂PLt, (1) where ε(u∗) denotes the infinitesimal strain tensor and A is the usual isotropic compliance tensor. We discuss systematic procedures of dimensional reduction of the three-dimensional prob-lem to two-dimensional plate models which proceed from variational formulations of the three