Anti theft measures for cycles stored in garages, sheds etc?

Recently, there were some thefts of all a family's cycles from their
garage which got me thinking about overnight security as quality
bicycles are not exactly cheap these days.

Would anyone like to tell me about their security arrangements of
their cycles when garaged overnight to prevent theft? Would an alarm
be the best or some arrangement to anchor cycles to concrete walls or
floors etc via locks.

Not the most the pleasant of subjects but it better than your pride
and joy going missing to be never seen again

Thanks for your comments

DC.