“What measures can we put in place to make sure that this doesn't happen again?”
Some employees who work for you made a mistake. You're not angry, but you want to avoid making this mistake in the future. You ask the group to figure out a way to avoid it.
What measures can we put in place to make sure that this doesn't happen again?
To "make sure" means to check something again, so that you know that it's OK. When you want something to happen and it's important, you check to "make sure" that it happens. For example, before your house guests leave, you can tell them:
Make sure you've got everything.
Or when someone is grilling some meat:
A more formal version of this phrase is "make sure that (clause)":
Make sure that the pork chops are cooked all the way through.
In a corporate office job, people are very careful not to make any mistakes, so they often talk about "making sure" of things.
We can use the word "measures" to talk about actions that you take in order to avoid mistakes or negative results. You "take" measures:
We've taken measures to prevent similar mistakes in the future.
You can also "put measures in place", which means to set up a system for avoiding mistakes:
At my previous job, I was responsible for putting measures in place to prevent electronic fraud.
After the measures have already been "put in place", then you can say that an organization "has measures in place":
The city government has measures in place for dealing with snow storms and other weather emergencies.