How to dehumidifying large unfinished basement?

[Byron W.]

I have a 3 unit building and the basement is dark, little ventilation and gets really humid. Which, I'm pretty sure is causing the first floor unit to be even more humid on warm days than it should be. The humidity levels in units 2 and 3 aren't nearly as bad as on the first floor unit (which is the one I'm currently house hacking). 

What's my best option for dehumidifying the basement long term? Thanks!

[Don Meinke]

'MOST' houses have low spots close to the foundation where over time the backfill has settled lower than normal ground level.  Filling that area so you have  a minimum of4 to 6" of slope in the first 2 feet.  Then 2-3 inches of slope for the next 2 feet.  IF their are ANY puddles within 10-20 feet of the house it is going to drain somehow back to the path of least resistance (aka your basement ).  Of course regrading your whole yard is first component of getting a dry basement.  You will  be surprised how much less your measure of humidity is in a basement by 'fixing' this problem 95% of all houses have.  Most people try to fight water intrusion from  the inside out, when the real way is to fight it outside in. (making LESS moisture to fight)