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Langmuir waves are often observed upstream of planetary bow shocks and interplanetary (IP) shocks. Waveform capture (WFC) measurements, obtained during Juno’s cruise phase, reveal the occurrence of Langmuir waves, as well as other wave modes, in association with IP shocks and IP coronal mass ejections (ICMEs) at distances from ∼1.3 to ∼5.4 au. This is a unique database of ICME/IP shock events with WFCs in the equatorial plane in these radial distances. We identified 12 events when WFCs were obtained within 36 hr upstream of the IP shock/ICME event (10 within less than 10 hr). Langmuir waves were observed at 9, a significantly higher occurrence than has previously been reported using spectral observations from other spacecraft. The larger rate is likely due to the bursty nature of Langmuir waves in combination with the higher time resolution of WFC data compared to spectral data. Observed peak amplitudes of ∼16 mV m ^−1 (peak to peak) are comparable to those observed upstream of outer planetary bow shocks. The highest peak amplitudes occurred in the strongest shocks (largest magnetic compression) and when waveforms were obtained closest to the shock. Langmuir waves were observed as much as 8 hr upstream. The WFCs provide electron density on rapid time scales, including an increase from ∼0.05 to 0.25 cm ^−3 in ∼0.01 s across an IP shock ramp. Although electron measurements were not obtained, these observations provide evidence for the energization of electrons at the shock or ICME front and, in some events, for propagation over large distances while maintaining the features in the distributions necessary to destabilize Langmuir waves.