I document the time-varying investment efficiency of conglomerates compared with single-segment firms. I find that, during recessions, conglomerates have higher Q-sensitivity of investment than do stand-alone firms, in contrast to the relationship during expansion periods. I also find that conglomerates, with the benefits from internal capital markets, exhibit increased dependence of investment on internal capital during recessionary periods, while stand-alone firms significantly increase cash retention and deviate their investment from its optimal level more severely. I examine the effect of the degree of diversification and find consistent evidence on investment efficiency and deployment of internal capital. I also provide evidence that conglomerates with stronger governance do not improve investment efficiency during recession, which suggests that agency costs cannot fully explain the changes in investment of conglomerates. Yolanda Yulong Wang