It is a Yucca and a lovely specimen too. probably Yucca filamentosa

Wow, that's spectacular!

Its not Yucca filamentosa, its Yucca gloriosa variegata.....wicked thorns on the leaf tips, but you probably know that already!

Its absolutely glorious! Congratulations! Does this kind die after flowering?

I knew someone would be able to get the correct name for this super plant.

Seaburngirl - they are great, but they do have a tendency to succumb to black spot infection, which the smaller varieties like filamentosa and flaccida seem less vulnerable to, in my experience.