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I have just started to use generics, and I am currently having a problem doing sorting on multiple fields. Case: I have a PeopleList as a TObjectList<TPerson> and I want to be able to make an Excel-like sorting function, by selecting one sort-field at a time, but keeping the previous sorting as much as possible. EDIT: It must be possible to change the field sort sequence at runtime. (Ie. in one scenario, the user wants the sort order A,B,C - in another scenario he wants B,A,C - in yet another A,C,D) Lets say we have an unsorted list of people : Lastname Age --------------------- Smith 26 Jones 26 Jones 24 Lincoln 34 Now if I sort by LastName : Lastname ▲ Age --------------------- Jones 26 Jones 24 Lincoln 34 Smith 26 Then if I sort by Age, I want this : Lastname ▲ Age ▲ --------------------- Jones 24 Jones 26 Smith 26 Lincoln 34 In order to do this, I have made two Comparers - One TLastNameComparer and one TAgeComparer. I now call PeopleList.Sort(LastNameComparer) PeopleList.Sort(AgeComparer) Now my problem is that this does not produce the output I want, but Lastname ? Age ? --------------------- Jones 24 Smith 26 Jones 26 Lincoln 34 where Smith,26 appears before Jones,26 instead. So it seems like it doesn't keep the previous sorting. I know that I can make just one comparer that compares both LastName and Age - but the problem is, that I then have to make comparers for each combination of the fields present in TPerson. Is it possible to do what I want using multiple TComparers or how can I accomplish what I want? New Years Update Just for reference to future visitors, this is (almost) the code

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