From Viz:

Now that she's 13 years old, it's time for young Kiki to start thinking about her future. So one night, under the shine of a full moon, she grabs her black cat Jiji, hops on her mother's broom and heads off into the night. The next day she alights upon a friendly oceanside city, and this, she tells her loyal and furry companion, is where she'll spend the next year learning how to become a real, honest-to-goodness witch.

But poor Kiki--there are a couple things she forgot to plan for. First, she's got to find a place to live. And, secondly, she's got to find a job!