This is the fifth in a series arXiv:1304.4508, arXiv:1305,6302, arXiv:1211.3259, arXiv:1305.6428 on the '\(k\)-shifted symplectic derived algebraic geometry' of Pantev, Toen, Vaquie and Vezzosi, arXiv:1111.3209. This paper extends the previous three from (derived) schemes to (derived) Artin stacks. We prove four main results: (a) If \((X,\omega)\) is a \(k\)-shifted symplectic derived Artin stack for \(k<0\) in the sense of arXiv:1111.3209, then near each \(x\in X\) we can find a 'minimal' smooth atlas \(\varphi:U\to X\) with \(U\) an affine derived scheme, such that \((U,\varphi^*(\omega))\) may be written explicitly in coordinates in a standard 'Darboux form'. (b) If \((X,\omega)\) is a \(-1\)-shifted symplectic derived Artin stack and \(X'\) the underlying classical Artin stack, then \(X'\) extends naturally to a 'd-critical stack' \((X',s)\) in the sense of arXiv:1304.4508. (c) If \((X,s)\) is an oriented d-critical stack, we can define a natural perverse sheaf \(P^\bullet_{X,s}\) on \(X\), such that whenever \(T\) is a scheme and \(t:T\to X\) is smooth of relative dimension \(n\), then \(T\) is locally modelled on a critical locus Crit\((f:U\to{\mathbb A}^1)\) for \(U\) smooth, and \(t^*(P^\bullet_{X,s})[n]\) is locally modelled on the perverse sheaf of vanishing cycles \(PV_{U,f}^\bullet\) of \(f\). (d) If \((X,s)\) is a finite type oriented d-critical stack, we can define a natural motive \(MF_{X,s}\) in a ring of motives \(\bar{\mathcal M}^{st,\hat\mu}_X\) on \(X\), such that whenever \(T\) is a finite type scheme and \(t:T\to X\) is smooth of dimension \(n\), then \(T\) is locally modelled on a critical locus Crit\((f:U\to{\mathbb A}^1)\) for \(U\) smooth, and \({\mathbb L}^{-n/2}\odot t^*(MF_{X,s})\) is locally modelled on the motivic vanishing cycle \(MF^{mot,\phi}_{U,f}\) of \(f\) in \(\bar{\mathcal M}^{st,\hat\mu}_T\). Our results have applications to categorified and motivic extensions of Donaldson-Thomas theory of Calabi-Yau 3-folds