There is provided herein a composition comprising: (A) a silanol and/orhydrocarbon-terminated polyorganosiloxane in an amount of from about 30 weight percent to about 90 weight percent; and, (B) a moisture curable silylated polyurethane resin in an amount of from about 10 weight percent to about 70 weight percent. There is also provided herein in another embodiment a two part sealant composition wherein the first part comprises: (A) a silanol and/or hydrocarbon-terminated polyorganosiloxane in an amount of from about 15 weight percent to about 60 weight percent, (B) a moisture curable silylated polyurethane resin in an amount of from about 2 weight percent to about 32 weight percent, and (C) a filler, said weight percents being based on the weight of the first part. In addition, there is provided herein a fumed silica composition comprising: (A) a silanol and/or hydrocarbon-terminated polyorganosiloxane in an amount of from about 20 weight percent to about 62 weight percent; (B) a moisture curable silylated polyurethane resin in an amount of from about 8 weight percent to about 38 weight percent; and, (C) a treated fumed silica in an amount of from about 5 to about 10 weight percent.