Every ancestor lived in a specific context at any given time. In order to make the best use of my time and your money, I need to know what you know about the ancestor you have asked me to research. To aid in that information transfer, I ask the following questions.
Who? I need the name of the person you wish researched. In case of women, I need their maiden name, unless this is the purpose of the search. I need nicknames, abbreviations, alternate spellings you have encountered. It is also helpful to have the names of spouses, parents, siblings, and children, if available.

What? This is the purpose or goal of your research. What do you want to learn about the person named? This also covers the format you wish to receive your new information. These are some of the formats available:
• a report on the sources I checked, what I found or didn’t find in those sources, a documented summary of findings, and suggestions for further research
• a documented narrative of findings
• a pedigree chart and family group sheet with sources attached
• a full-blown ascending or descending genealogy covering multiple generations
• You want to discuss the format with your genealogist to help you decide

When? Each ancestor lived in a specific time. I need to know his birth and death dates or close approximations. This question also addresses the date you need your project completed. I cannot give you a complete genealogy for Christmas if you ask me at Thanksgiving. Quality research takes time.

Where? Each ancestor lived in a specific location. At minimum, I need to know the state to have a starting point for research. The more detailed the location you give me, the more focused the research becomes.

Why? Each ancestor had a motive for his specific behavior. Why he did something is the hardest of the questions to answer. He married the girl next door before he left for war, moved to the frontier, eloped because of parental disapproval of the marriage. This question also requires the genealogist to research the social context of his life at that time and place.

How? How do you know what you know? I need to see copies of the documents you have already searched for my own analysis and planning. It costs me time and you money when I have to reproduce work you have already done and not shared with me.
Look at a modern example. My husband and I were married in one county in Oklahoma and the marriage recorded in two counties, one of which neither of us ever lived. How do I know this? Two official documents shed light on this event. One is the marriage certificate issued by the church, the other the state’s official certificate of marriage. The church marriage certificate states that Errol D. Douglass wed Mary Anne Clement, 24 June 1966 at the Church of the Immaculate Conception, Oklahoma City, Oklahoma. Witnesses were Bill Robertson and Leann Grizzle. The officiant was Fr. John Mickaleska. The state certificate gives the home of the groom as Holdenville, Hughes County, Oklahoma. The bride lived in Oklahoma City, Oklahoma County, Oklahoma. The groom was age 20, the bride age 21. The officiant recorded this event in Woodward County, Oklahoma. Why record this event in Woodward County when neither bride nor groom resided there? You would have to search the career of the priest for the answer. This small family wedding was his last duty at the Church of the Immaculate Conception. The wedding was on a Friday night and the priest was to assume his new duties the following day in Woodward. He recorded this marriage in the nearest courthouse on the following Monday. That courthouse was in Woodward County. The courthouse clerk then returned the marriage certificate to the courthouse in Oklahoma County.