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diff --git a/Source/FieldSolver/SpectralSolver/SpectralSolver.H b/Source/FieldSolver/SpectralSolver/SpectralSolver.H
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+++ b/Source/FieldSolver/SpectralSolver/SpectralSolver.H
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+#ifndef WARPX_SPECTRAL_SOLVER_H_
+#define WARPX_SPECTRAL_SOLVER_H_
+
+#include <SpectralKSpace.H>
+#include <PsatdAlgorithm.H>
+#include <SpectralFieldData.H>
+
+/* \brief Top-level class for the electromagnetic spectral solver
+ *
+ * Stores the field in spectral space, and has member functions
+ * to Fourier-transform the fields between real space and spectral space
+ * and to update fields in spectral space over one time step.
+ */
+class SpectralSolver
+{
+    public:
+        // Inline definition of the member functions of `SpectralSolver`
+        // The body of these functions is short, since the work is done in the
+        // underlying classes `SpectralFieldData` and `PsatdAlgorithm`
+
+        /* \brief Initialize the spectral solver */
+        SpectralSolver( const amrex::BoxArray& realspace_ba,
+                        const amrex::DistributionMapping& dm,
+                        const int norder_x, const int norder_y,
+                        const int norder_z, const bool nodal,
+                        const amrex::RealVect dx, const amrex::Real dt ) {
+            // Initialize all structures using the same distribution mapping dm
+
+            // - Initialize k space object (Contains info about the size of
+            // the spectral space corresponding to each box in `realspace_ba`,
+            // as well as the value of the corresponding k coordinates)
+            const SpectralKSpace k_space= SpectralKSpace(realspace_ba, dm, dx);
+            // - Initialize the algorithm (coefficients) over this space
+            algorithm = PsatdAlgorithm( k_space, dm, norder_x, norder_y,
+                                        norder_z, nodal, dt );
+            // - Initialize arrays for fields in Fourier space + FFT plans
+            field_data = SpectralFieldData( realspace_ba, k_space, dm );
+        };
+
+        /* \brief Transform the component `i_comp` of MultiFab `mf`
+         *  to spectral space, and store the corresponding result internally
+         *  (in the spectral field specified by `field_index`) */
+        void ForwardTransform( const amrex::MultiFab& mf,
+                               const int field_index,
+                               const int i_comp=0 ){
+            BL_PROFILE("SpectralSolver::ForwardTransform");
+            field_data.ForwardTransform( mf, field_index, i_comp );
+        };
+
+        /* \brief Transform spectral field specified by `field_index` back to
+         * real space, and store it in the component `i_comp` of `mf` */
+        void BackwardTransform( amrex::MultiFab& mf,
+                                const int field_index,
+                                const int i_comp=0 ){
+            BL_PROFILE("SpectralSolver::BackwardTransform");
+            field_data.BackwardTransform( mf, field_index, i_comp );
+        };
+
+        /* \brief Update the fields in spectral space, over one timestep */
+        void pushSpectralFields(){
+            BL_PROFILE("SpectralSolver::pushSpectralFields");
+            algorithm.pushSpectralFields( field_data );
+        };
+
+    private:
+        SpectralFieldData field_data; // Store field in spectral space
+                                      // and perform the Fourier transforms
+        PsatdAlgorithm algorithm; // Contains Psatd coefficients
+                                  // and field update equation
+};
+
+#endif // WARPX_SPECTRAL_SOLVER_H_