Electromagnetic theory: design	Integration of classical and quantum methodologies combining charge transfer, quantum effects, and classical inhomogeneous enhancements in the complex molecule–substrate.
Theory: modeling	Generally available modeling/simulation tools for realistic SERS substrate configurations and for the accurate determination of Raman spectra of molecules possibly present in observations.
Stimulated and quantum SERS	Exploitation of stimulated Raman processes (e.g., involving multiple incident wavelengths) and the single-photon nature of the inelastic Raman emission for surface-enhanced imaging and spectroscopy.
Substrate benchmarking	Development of standardization protocols for the characterization of plasmonic (macroscopic and colloidal) substrates and evaluation of SERS performance.
Substrate fabrication	Reliable methods for the synthesis/fabrication of uniform, highly reproducible, and efficient enhancing substrates, with a high degree of structural precision and robust, quantitative SERS response within specification limits (to be established).
Reliability	Proof of SERS performance, preferentially using nonresonant molecules (established reporters) and in the absence of charge-transfer resonances.
Labeling and analyte access	Development of a methodology to determine the density and localization of molecules (including target molecules, surfactants, ions, eventual contaminations, etc.) accurately with ultraresolution in space (nm or better) and time (sub-picosecond), capable of tracing the dynamics of Raman processes in situ and in real time.
Analysis in real environments	Rational design, careful characterization, and modeling of (functionalized) SERS substrates or tags in real environments/under real conditions, leading to general rules for applicability of SERS substrates in various fields.
Data processing and quantification	Development of standardized protocols and data processing for (multiple) analyte quantification for different application strategies (with labels, label-free as well as using complex statistical models for unknown compositions).
Clinical translation	Clinical translation of SERS nanoparticles for in vivo human applications.