It can be locked, but you will need a small padlock. This is not included in the scope of delivery.

As it's a cabin bag, it's not essential to lock the compartment if you keep it close by, otherwise it's really great, well thought out, practical and solid. I'd take the same bag again without hesitation.

Unfortunately the front pocket does not lock so yes, you need a separate lock for that.

The front compartment has a zip. You would have to organise a small lock yourself.
However, the suitcase is super practical, smooth-running, has a good compartmentalisation in my experience and is suitable for most airlines as an onboard suitcase. would buy it again