We discuss measurements of convoy electrons performed with incident (50, 150 keV) and (100, 200, 400 keV) ions, in coincidence with charge-analysed projectiles emerging from thin (150 - ) C and Cu foils. A strong dependence of convoy electron yields on the projectile charge, as well as cusp-electron spectra in coincidence with neutrals are observed and compared with the characteristics of presently available models for beam - foil convoy electron emission. Measurements performed with sputter-cleaned target surfaces confirm that the transmission through the surface potential is important in determining both the coincident convoy electron yields and the final charge distribution of the emerging projectiles.