I have Brunerra 'Jack Frost' and Lamium maculatum 'Beacon Silver' as ground cover in a shady corner of the woodland garden and wonder if anyone could suggest a silver leaved shrub to give some height

Hi Bernard. Most shrubs with silver leaves are silver or grey because they like good light in fact full sun rather than shade. Depending on just how shaded the area is you could try the very adaptable Cotoneaster franchettii.

what about a white/green euonymous [spelling?]

Or Elaeagnus 'Quicksilver' which is tolerantof less sun than many. Phil J

Thanks for the suggestions.