We study the distribution of stars, HII regions, molecular gas, and individual giant molecular clouds in M33 over a wide range of spatial scales. The clustering strength of these components is systematically estimated through the fractal dimension. We find scale-free behavior at small spatial scales and a transition to a larger correlation dimension (consistent with a nearly uniform distribution) at larger scales. The transition region lies in the range ∼ 500 − 1000 pc. This transition defines a characteristic size that separates the regime of small-scale turbulent motion from that of large-scale galactic dynamics. At small spatial scales, bright young stars and molecular gas are distributed with nearly the same three-dimensional fractal dimension (D f,3D 1.9), whereas fainter stars and HII regions exhibit higher values D f,3D ≃ 2.2 − 2.5. Our results indicate that the interstellar medium in M33 is on average more fragmented and irregular than in the Milky Way.

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