  The BICEP/$\textit{Keck}$ (BK) series of cosmic microwave background (CMB)
polarization experiments has, over the past decade and a half, produced a
series of field-leading constraints on cosmic inflation via measurements of the
"B-mode" polarization of the CMB. Primordial B modes are directly tied to the
amplitude of primordial gravitational waves (PGW), their strength parameterized
by the tensor-to-scalar ratio, $r$, and thus the energy scale of inflation.
Having set the most sensitive constraints to-date on $r$, $\sigma(r)=0.009$
($r_{0.05}<0.036, 95\%$ C.L.) using data through the 2018 observing season
("BK18"), the BICEP/$\textit{Keck}$ program has continued to improve its
dataset in the years since. We give a brief overview of the BK program and the
"BK18" result before discussing the program's ongoing efforts, including the
deployment and performance of the $\textit{Keck Array}$'s successor instrument,
BICEP Array, improvements to data processing and internal consistency testing,
new techniques such as delensing, and how those will ultimately serve to allow
BK reach $\sigma(r) \lesssim 0.003$ using data through the 2027 observing
season.
