Note that think tanks and research institutes may have a (or multiple) specific policy perspective (i.e. centrist, liberal, conservative, feminist, libertarian, etc).
About think tanks - On Think Tanks
Starting in 2025, many US government websites and datasets are "under review" and may not be available at their original location (this includes foreign and international info housed by federal agencies). There are a number of organizations working to make those sites and data available. If you need something that used to be available and is no longer, please email Lorena (see left-hand margin - there is a mail button) - she may be able to assist you in locating a mirrored source for the information.