Nebular spectroscopy is a valuable tool for assessing the production of heavy elements by slow neutron(n
)-capture nucleosynthesis (the s
-process). Several transitions of n
-capture elements have been identified in planetary nebulae (PNe) in the last few years, with the aid of sensitive, high-resolution, near-infrared spectrometers. Combined with optical spectroscopy, the newly discovered near-infrared lines enable more accurate abundance determinations than previously possible, and provide access to elements that had not previously been studied in PNe or their progenitors. Neutron-capture elements have also been detected in PNe in the Sagittarius Dwarf galaxy and in the Magellanic Clouds. In this brief review, I discuss developments in observational studies of s
-process enrichments in PNe, with an emphasis on the last five years, and note some open questions and preliminary trends.
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