Joanna, an animal lover and latchkey child, doesn't mean to run away -- ""at least not exactly."" She just hides in Mr. Lauro's vegetable cart so she can ride along behind Costanza, his horse, but doesn't get a chance to sneak out until they arrive at Mr. Lauro's home. Having gone that far Joanna stays in hiding until late at night, when she decides to find a nice green field for her and Costanza to live in. Costanza, however, prefers his home, and after Mr. Lauro wakens and drives Joanna to hers in the wagon (up front this time -- and ""the most wonderful thing that had ever happened to her"") it looks like Joanna too belongs somewhere. For waiting to welcome her is the whole neighborhood, including her worried working mother (who is ""not even mad"") and the little boy downstairs who needs Joanna's advice on his sick turtle. A minimal candidate for the regular fiction shelf, but La Farge's tender realism, reinforced by Hyman's soft tan Brooklyn scenes, offers something new in the easy reader format.