Here's a short CTE, assuming a table named #Employees with the data shown in the article:

WITH OrgChart (UserID, LastName, FirstName, ManagerUserID)

AS

(

    SELECT UserID, LastName, FirstName, ManagerUserID

    FROM #Employees

    WHERE ManagerUserID = 0

    UNION ALL

    SELECT e.UserID, e.LastName, e.FirstName, e.ManagerUserID

    FROM #Employees e

    INNER JOIN OrgChart o

    ON e.ManagerUserID = o.UserID

)

SELECT UserID, LastName, FirstName, ManagerUserID

FROM OrgChart;

Please excuse any typos - I had to retype this in here.