This should point you in the right direction... post back here if you run into any difficulty.
declare @table table (primaryID int, ForeignID int, Stage varchar(10), UpdatedDate datetime)
insert into @table
select 1, 70, 'Start', '4/10/06 11:00:01' union all
select 2, 70, 'Middle', '4/10/06 11:30:01' union all
select 3, 70, 'Middle', '4/11/06 9:00:00' union all
select 4, 88, 'Start', '4/20/06 10:23:00' union all
select 5, 88, 'Start', '4/21/06 12:32:05' union all
select 6, 88, 'End', '4/21/06 12:50:00'
select * from @table
select ForeignID, Stage, Min(UpdatedDate) UpdatedDate
from @table
group by ForeignID, Stage
order by 1,3
Nathan Skerl