Illinois will obviously have their own rules if they pass conceal carry. In most states that have shall issue, the basic requirements are the same as for buying a gun, no felonies, forced mental health confinements, current indictments etc. In addition many states add requirements that are stricter such as no misdemeanor drug convictions in the last 5 years, things of that nature. In addition some states have training requirements that vary from none like Indiana to simple safety courses like Virginia to more elaborate systems like Texas that have marksmanship qualifications. In may issue states where the permit is up to the discretion of a local judge or sheriff the requirements may be even less, and in some may issues states or parts of states the judges and sheriffs are very free at handing out permits in others it is nearly impossible to get one.