Moore was made redundant by young people's housing and training charity Patchwork in May, where she held a similar role, after it began merger talks with the Community Housing Association. She was previously development manager at Action on Addiction.
Moore said her role would be to oversee the targeting of high-value donors and prepare for the charity's anniversary event at the House of Lords next year.
She replaces Vicky MacNichol, who left to freelance.
Activity to target corporate donors over Christmas was being planned, Moore added, as were media relations campaigns aimed at the London regional and Catholic press.
As well as providing accommodation to young homeless Londoners, the charity provides counselling, education and training in practical skills.