There are many species of ladybird in the UK, all of which are harmless. Since 2005 we have seen the rise of the Harlequin ladybird, a species which was introduced from the Far East to control aphids in greenhouses, and is now living wild.
Ladybirds live happily on the outside of buildings, but for a few weeks in autumn will come inside in clusters. This often causes concern for homeowners. They can be controlled by use of residual sprays such as Dethlac or powders such as Residex P which can be sprinkled into cracks and crevices where they congregate