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First, to what accuracy can time delays be measured from individual double- or quadruply-imaged systems for which the sampling rate and campaign length are given by LSST? Simple techniques like dispersion minimization {\bf (GGD: Chris, what is this technique officially called and are there good references???)} or spline interpolation through the sparsely sampled data [REFS?] yield time delays which are likely to be too inaccurate, while more complex algorithms such as Gaussian Process modeling [REFS] hold more promise. Regardless, it is presently unclear whether the long baseline of surveys like LSST ($\sim10$ years) can yield very accurate time delays despite the somewhat poor sampling ($\sim10$ days). Second, do $\sim1000$ reasonably measured time delays from LSST yield competitive constraints on $H_0$ compared to one or two very well studied systems [REFS].\footnote{There is of course the additional complexity that it not yet clear to what extent ``follow up'' observations will be needed on the LSST lens systems. Certainly, following up all systems to the degree that, for example, [REF] did for B1608+656 to derive the most stringent lensing constraints on $H_0$ is clearly not feasible. This is a complex issue and beyond the scope of the persent paper.}  . what are some Of course, the later question cannot be answered without the former, and so the goal  of this work is to present a ``Time Delay Challenge'' (TDC) to  the issues community in an effort to assess the present ability of time series analysis algorithms to measure accurate time delays in the face of realistic light curves that will be obtained  with measuring LSST. In \S \ref{sec:light_curves} we describe the mock light curves that we have generated for the challenge, including some of the broad details of observational and physical effects that may make extracting accurate  time delays to difficult, without giving away information that will not observationally knowable during or after  the required precision?     . why issue a challenge? LSST survey. In \S \ref{sec:structure} we describe the structure of the challenge, how interested groups can access the mock light curves, and what the final criterion for ``success'' will be. {\bf (GGD: what is the criterion for success???)}