There are three ways to reach an expert, and they suit different situations.
Let matching come to you
Post the project and wait for proposals. Best when you are open about approach and want to compare how different experts would tackle it.
Browse the directory
Experts in the sidebar lists available researchers by field. Best when you already know the discipline and want to read profiles before committing to a brief.
Ask AI matching
AI Matching lets you describe what you need in plain language and returns a shortlist with a reason for each suggestion. Best when you are not sure what kind of specialist your problem needs, which is a common and entirely reasonable position.
Judging a profile
Look at the methods, not the adjectives. Check that the stated qualification is evidenced, that the publications are real and relevant, and that the reviews describe work like yours. An expert with three strong reviews in your exact method is worth more than one with thirty in unrelated fields.