Which famous songs did Robert Lamm write for Chicago?

1. Lamm as one of Chicago’s chief songwriters — the basics

Robert Lamm was a founding member of Chicago and authored many of the group’s key early songs; Songwriter Universe’s interview lists multiple classics he wrote or co-wrote, and notes he contributed seven songs to Chicago’s debut album ^[1]. The band’s official site and profiles reinforce his long tenure and central role as keyboardist, vocalist and arranger, underlining that his songwriting shaped Chicago’s identity as “the rock band with horns” ^{[3] [4]}.

2. The headline hits Lamm is most often credited with

Contemporaneous and retrospective accounts repeatedly cite several Lamm compositions as signature Chicago songs: "25 or 6 to 4," "Saturday in the Park," "Does Anybody Really Know What Time It Is?," and "Beginnings" are all named directly in interviews and band retrospectives as Lamm songs ^{[4] [1]}. Publications and rankings discussing Chicago II and other early albums also associate Lamm with "Make Me Smile" and "Colour My World," which helped give the band multiple Top 10 entries from the same record ^{[2] [1]}.

3. Context: which songs came from which eras and albums

Songwriter Universe and in-depth album pieces explain that many of Lamm’s best-known songs come from Chicago’s late-1960s/early-1970s run — notably Chicago Transit Authority (their debut), Chicago II, and Chicago V — periods that produced multiple Top 10 singles and cemented the band’s commercial breakthrough ^{[1] [2]}. That era is where Lamm’s mix of socially aware lyrics, melodic hooks and horn arrangements became a defining template for the group ^{[2] [1]}.

4. What Lamm himself and band pages emphasize about his contributions

Interviews with Lamm stress not only songwriting but arranging horns and singing lead on many of his compositions; the Grammy profile and Chicago’s official site note his ongoing role as a frontman and arranger across decades ^{[4] [3]}. Lamm has also spoken about writing songs late at night (the origin story often told for "25 or 6 to 4") and about contributing a substantial portion of material on early records ^{[2] [1]}.

5. Beyond the biggest singles: other Lamm compositions and deep cuts

Reporting and discographies show Lamm’s catalog inside Chicago is extensive: in addition to the marquee singles, his credits include "Dialogue (Part 1 & 2)," "Free," "Harry Truman," "Another Rainy Day in New York City," and many album tracks and later-period songs — he wrote or co-wrote seven tracks on the debut and continued contributing through subsequent decades ^{[1] [3]}.

6. Reputation, accolades and later perspective

Profiles note Lamm’s songwriting has been formally recognized: Chicago and its members have been honored (e.g., Rock & Roll Hall of Fame recognition for the band in 2016 noted in interviews), and Lamm’s persistent presence in the group is repeatedly cited as key to their longevity ^{[1] [3]}. Grammy.com’s piece frames Lamm as a long-running creative center whose songs like "25 or 6 to 4" and "If You Leave Me Now" are part of the band’s instantly recognizable canon — though "If You Leave Me Now" is usually associated with Peter Cetera as writer; available sources do not claim Lamm wrote that particular Cetera ballad ^[4].

7. Limitations of this summary and areas of disagreement

My answer relies on the provided interviews, band pages and retrospectives; these sources consistently credit Lamm with many early Chicago hits, but they sometimes bundle band-wide accomplishments without itemizing every songwriting credit ^{[4] [1]}. For precise songwriter attributions on every Chicago single (especially songs often associated with other members, like Peter Cetera’s “If You Leave Me Now”), consult full album liner notes or authoritative catalog listings — available sources do not provide a complete, track-by-track legal songwriting ledger here ^{[4] [1]}.

8. Quick takeaway for listeners and researchers

If you want the short list of famous Chicago songs written by Robert Lamm, start with "25 or 6 to 4," "Saturday in the Park," "Does Anybody Really Know What Time It Is?," "Beginnings," "Make Me Smile" and "Colour My World" — all are repeatedly credited to him in interviews and band histories ^{[1] [2]}. For an exhaustive, official songwriter breakdown, check album credits or music-rights databases; the interviews and band bios cited here are authoritative in naming Lamm as one of Chicago’s principal songwriters ^{[1] [3]}.