A multivalue field can do exactly what you want: a multi-selectable combo box.  Richard covers the basic in his free video ( https://www.youtube.com/watch?v=z_9zv3GbyKk ).  The basics cover how to set up a multivalue field.  But the essential thing is to know how to query info from multivalue fields, and that is not basic at all.  I don't have access to Richard's paid videos ( https://599cd.com/blog/display-article.asp?ID=2260 ), so I don't know if they cover queries or not.  So let me give you an example.

In the first picture below, I have a table containing people's movie preferences.  John loves animation, drama, horror, and musical; Joe prefers comedy, drama, and western, and so on.  The "category" field is a multivalue field that allows multiple values, which you select from the combo box.  Again, you need to watch Richard's free video to know how to set this up in table design (not very difficult).

If you want to make a query to find out which persons loves drama (DR), you can't use the regular SELECT... WHERE query, because that only works with "single value" fields.  You need to write the query like the second picture below.  You need to use the ".Value" property to refer to each individual value of the category field.  You need to use a "query within a query" to check through all the individual values of the category field to find "DR" -- because a multivalue field is like "sub-table" that you need to separately query for.  Lastly, you need to know how to use "aliases" in such a query (Table1 AS t, Table1 AS t2), because Table1 is referred to twice.

This is fairly complicated as you see, and that's why multivalue fields are one of Richard's "Evil Access Stuff" ( https://599cd.com/blog/display-article.asp?ID=1718 ).  And I actually agree.  But if it works for you, if you can overcome its technical difficulty (which is present in everything in Access anyway), it doesn't matter.

Thank you Kevin, I will it it a try