A turbine comprising: a housing ; a turbine shaft rotatably supported in said housing and extending along a centerline axis ; and a plurality of turbine stages located along said turbine shaft and contained within said housing , each turbine stage comprising: a rotor coupled to said turbine shaft , said rotor comprising a bucket extending radially outward therefrom; a shroud , said shroud comprising: an alignment member coupled to the housing and comprising a first end , a second end , and a body extending between said first and said second ends, said second end comprising an arcuate portion configured to facilitate leakage flow downstream from the bucket ; characterised in that said body comprises a first groove , and a second groove downstream from the first groove , wherein the second groove comprises: an upstream radially and circumferentially extending side wall ; a downstream radially and circumferentially extending sidewall ; and a circumferentially extending end wall 148 that extends axially between radially outer ends of the upstream side wall and the downstream sidewall ; wherein the second end comprises a profile comprising the arcuate portion, the profile extending axially from a radially inner end of the downstream sidewall ; and wherein a seal is coupled to said body to facilitate sealing a gap defined between the bucket and said body . a housing ; a turbine shaft rotatably supported in said housing and extending along a centerline axis ; and a plurality of turbine stages located along said turbine shaft and contained within said housing , each turbine stage comprising: a rotor coupled to said turbine shaft , said rotor comprising a bucket extending radially outward therefrom; a shroud , said shroud comprising: an alignment member coupled to the housing and comprising a first end , a second end , and a body extending between said first and said second ends, said second end comprising an arcuate portion configured to facilitate leakage flow downstream from the bucket ; characterised in that said body comprises a first groove , and a second groove downstream from the first groove , wherein the second groove comprises: an upstream radially and circumferentially extending side wall ; a downstream radially and circumferentially extending sidewall ; and a circumferentially extending end wall 148 that extends axially between radially outer ends of the upstream side wall and the downstream sidewall ; a rotor coupled to said turbine shaft , said rotor comprising a bucket extending radially outward therefrom; a shroud , said shroud comprising: an alignment member coupled to the housing and comprising a first end , a second end , and a body extending between said first and said second ends, said second end comprising an arcuate portion configured to facilitate leakage flow downstream from the bucket ; characterised in that said body comprises a first groove , and a second groove downstream from the first groove , wherein the second groove comprises: an upstream radially and circumferentially extending side wall ; a downstream radially and circumferentially extending sidewall ; and a circumferentially extending end wall 148 that extends axially between radially outer ends of the upstream side wall and the downstream sidewall ; an upstream radially and circumferentially extending side wall ; a downstream radially and circumferentially extending sidewall ; and a circumferentially extending end wall 148 that extends axially between radially outer ends of the upstream side wall and the downstream sidewall ; wherein the second end comprises a profile comprising the arcuate portion, the profile extending axially from a radially inner end of the downstream sidewall ; and wherein a seal is coupled to said body to facilitate sealing a gap defined between the bucket and said body . <EOS>